COMPUTER FOR NEW GENERATION
UNIVERSAL BASIC EDUCATION UBE
WITH WORK SHEET
TABLE OF CONTENTS
LESSON NOTE\CLASSESS OF COMPUTERS
THE COMPUTER SYSTEM
CARE FO COMPUTERS
CLASSES OF COMPUTER
It is virtually impossible to definitely categorize computer by size, cost or scope.
For example, even computer manufacturers do not always agree on what distinguishes a minicomputer from a microcomputer.
This lack of standard method of categorizing computers has resulted in a significant amount of confusion for users. This lesson classifies computers according to:
- The type of data they have
- The size and speed of operation
- The generation
- The number of purpose
At the end of this lesson, you should be able to:
- Identify the compute by type, size, generation and purpose
- List the example of the various classes of computer.
CLASSIFICATION BASED ON DATA REPRESENTATION
Here, we mean the ways the computer are grouped due to the data they work on. We have three types of computer and they are:
- Analog computer
- Digital computer
- Hybrid computer
These computers are used for scientific works. They handle data that change from time to time.
Analog computers handle data in form of varying signal/quantity that assume and infinite number of level during variation. i.e it works by measuring changes in continuous physical or electrical state rather than counting. Such measurements as temperature, voltage, volume, chemical composition of petroleum products, amounts of current flowing through an electrical current etc. are used e.g. petrol pump, speedometer, Thermometer etc.
Thermometer is used to measure the temperature (data) of a body.
Let’s take for example a patient in the hospital. This patient’s temperature (data) is not fixed; it changes always from time to time.
Analog computers are used by scientist. The Doctors and nurses that use thermometers in the hospitals are scientists. The engineers that manufacture the speedometer are Scientists. Analogh computers and machines are used in different places, such as school laboratorie factories, etc.
The digital computers are the ones that work on number (digits). They solve problems by working on numbers. i.e. they can be used for arithmetical operations, such as addition, subtraction, multiplication and Division. They can as well be used for comparison.
These computers are used mostly in business are of life. A good example of a digital machine is the calculator that is used for simple and difficult calculation E.g Laptop, Palmtop, Desktop, Calculator.
DIAGRAM OF LAPTOP, DESKTOP, PALMTOP
Most computers that we see around are digital computers, they are common n offices, schools, supermarket, business centers, cyber cafes, etc.
These computers combine the properties of analog and digital computer. That is, they can do analog computation as well as digital computation. Let’s take a modern day television set as an example. When you select a channel 9digital), you then fine time until it shows the station you want clearly (analog), you then store the station (digital). This is a good illustration of hybrid device.
DIAGRAM OF TV
Hybrid computers are net too common, an example is a robot used in an industrial environment. Another good example is the computer used in launching rocket into the space
- An example of Analog machine is ___________
- The calculator is a good example of __________ machine
- The digital computers can perform additions and subtraction Yes or No____
- The digital compute rare used in ____ areas of life.
- The digital computers cannot perform multiplication and division yes or No ______
- ___________ Computer can do both analog and digital jobs.
- The computer used to control robot is ____ computer.
- The Analog computers can measure speed Yes or No.
- Analog computer cannot be used to measure the result of the experiment.
- Rain gauge is not a good example of analog computer. (A) True (B) False.
CLASSIFICATION ACCORDING TO SIZES AND SPEED OF OPERATION
In this case, we split computers into four broad streams as follows:
These are computer systems with enormous power and size. They are largest, faster and most expensive of all computers. These are otherwise known as “SUPER OR MAXI” computers e.g. CRAY X/Y.
- These machines are special, high-capacity computers used by very large organization
- They are employed for scientific and military research.
- They are also used to track and control space exploration, for oil exploration, and worldwide weather forecasting.
This are the larger computer that requires specially wired, air-conditioned rooms. They are capable of great processing speeds and data storage.
They are employed by large organizations such as banks, business organizations, universities and government agencies to handle millions of transactions.
These are also known as “medium/mid -rages computer ’
They fall between mainframe and micro computer in their processing speed and data storing capacity .they possess all features of main frame but at a lower capacity.
Medium-size companies or departments of large companies typically use them for specific purpose to do research or to monitor a particular manufacturing process, also used for data processing needs such as accounting.
Diagram of micro computer
Micro computers are at present the most popular computers. They are very small and there are different kinds of micro computers, e.g. Desktop, Laptop, Notebook and Palmtop.
All micro computers have keyboard (which looks like typewriter), monitor (that looks like television),
Micro computers are also known as the personal computers (pc). They are found in different places, such as homes, offices, schools etc.
This is a category of micro computer that can be set on the top of a desk It supports other peripherals and has very high storage capacity and speed.
This is a mobile micro computer, that is, it can be carried about. It is in form of a briefcase.
This computer is used mostly by the business men.
The notebook too is a mobile computer. It is not as big as the laptop. It has the size of the notebook used in writing. The businessmen use the notebooks too.
They are small enough to be held in the palm of your hand.
They are equally as powerful as the Desktop.
- The largest, faster and most expensive of all computer is __________
- Another name for monster computer is __________
- Monster computer can be used for __________
- _____ Computer is the smallest.
- The weather forecaster uses the __________ computer.
- Mainframe computer works well in an __________ environment.
- The banks and larger organization make use of _________ computers.
- Four examples of micro computers are _____, _____, _____, _____.
- The type of micro computer that look like a brief case is called _________?
- The label in the palm is called ___________,
CLASSIFICATION OF COMPUTER BY GENERATION
A specific thing is said to belong to a specific “Generation”.
In the electronic Computer world, we measure advancement of technology by generations. Each generation are UNIVAC,IBM 330 etc.
- The computers of the Second generation existed between 1950 to 1964.
- There were large but not as the first generation computers, and were built with TRANSISTORS instead of vacuum tubes.
- Transistors were smaller, less expensive.
- The computer in the generation generated lesser heat compared to the first generation.
- The use of mitotic oxide semi-conductor in building their memories increase processing speeds and reliability.
- Examples of computers in this generation are. Honey well 800, IBM 7030 etc.
THIRD GENERATION OF COMPUTER
DIAGRAM OF INTEGRATED CIRCUIT
- The computers of this generation existed between 1964 and 1975.
- It was built using integrated circuit (IC)
- This reduces the physical size of the computer.
- The circuits were made of resistors, diodes, and transistors.
- The components with which the circuits were built gave the circuit very high speed than the earlier generation.
- The small size of the circuits mad3e the computer to be portable and prevented then from occupying much space.
- Examples of computers in this generation are: Honey well 1120, IBM 705.
- The computers of this generation were from 1975 and 1982.
- The major components were built with large scale integrated circuit.
- As a result of technological advancement these computers are smaller in physical size and lower in cost.
- They generated lease amount of heat
- They have large memory and storage capacities.
- They are called micro computers and mini computers.
- The fifth generation were from 1990 till Date.
- It uses artificial intelligence
- The system is capable of performing functions of human experts.
- Solving problems that require humans intelligence, judgement etc.
- Example is ROBOT.
CLASSIFICATION OF COMPUTER BY PURPOSE
Computer exist as special and general purpose.
SPECIFIAL PURPOSE COMPUTER
These Were Designed to Perform One Specific task such as Scientific work, or Word processing .The Programs of instruction is built into the machine and this ,once booted ,goes straight to the configure mode
They have merit of performing the job economically ,quickly and effectively .example production control of air lanes ,weather study and forecast ,automobile ; thermometer ,micro state ,micro wave ovens et c,
GENERAL PURPOSE COMPUTER
These are also called multi-purpose computer and used for verity to store various program=ms of instruction, perform a variety of operations such as integrated processing, graphics, database etc.
Most computers are general purpose machines as they can handle many different kinds of tasks.
- There are ______ generations of computers.
- The first generation of computer uses ____________________
- Second generation computers were between _________ and __________.
- Second generation computers were built with __________________
- One example of the second generation computer was ________________________.
- The third generation of computer was built using ________________________.
- The components of the fourth generation computers were buitlt with __________________________.
- ________________________ generation of computers produces highest rate of heat._________________________________.
- The fifth generation of computer uses ____________________________________.
- Example of the fifth generation of computers was ____________________________.
- Computer classification base on purpose has two major type, they are __________________________________________ and _______________________________.
THE COMPUTER SYSTEM
A computer is a special multi-purpose electronic device (machine) that is capable of receiving instruction (data), storing and processing it and giving a described result as output accurately at an incredibly high speed.
At the end of this lesson, you should be able to:
- Explain the term computer system;
- State the components of a computer system;
- Explain the term: Hardware, software, users;
- Type with computer
Meaning of computer system:
The computer is an information machine that can store, retrieve and process data.
The computer as a system is a set of inter-related / components aimed at achieving the same goal.
Diagram of a computer system:
The computer as a system is made up of;
Hardware is the physical part of the computer components, which make up the computer configuration.
There are three major components of computer hardware namely;
The input, output devices and system unit.
Example of hardware are:
Keyboard, mouse, light pen, joy stick, monitor, printer etc.
Diagram of computer with an operator
These are instructions that directs hardware about what to do and how to do it . OR
The software refers to the programs, which are processed by the hardware. A program is a sequence of instructions that are carried out by the Hardware to solve given problems or to perform given tasks. Computer cannot do anything unless directed to do so by a person.
System software are programs that come with the computer to assist in the use of the hardware.
We say they make the computer operational. These are non-hardware aids namely computer programs and routines that facilitate the operation of the computer.
Application programs are software that are designed to be put to specific practical use. This broad classification may be further sub-divided into: customized application programs and standards application packages.
COMPUTER USERS: – Diagram
Computer users are those who make use of computer to perform day to day activities. Example of computer users are:
- Computer policy makers
PROGRAMMERS – diagram
A computer programmer is the one who write compute programs.
Computer programs are set of instructions which the computer follows to solve a given problem. They tell the computer what to do.
OPERATORS – diagram
The computer operator handles and operates the computer on day-to-day basis. He works directly with the computer units.
Some of the jobs an operator uses the computer for are:
- TYPING: A computer operator uses the computer to type letters, reports, memos.
- DESIGNING: A computer graphic operator uses the computer to design graphics. He also uses it to draw images. The computer graphic operator is also known as graphic artist.
- CONTROLLING: A computer operator uses the computer to control heavy equipment, robots in industrial areas.
COMPUTER POLICY MAKERS
These are those who make laws concerning the manufacture and use of computer.
- Computer is a machine that can ______, ________ and _________
- Computer as a system is made up of _______, ________ and ____
- The physical part of the computer component is called _________
- Mention four example of hardware: (i) ___________ (ii) _________
(iii) ____________ (iv) _________________
- Software are programs which are processed by __________________
- Two types of software are _________ and ________________
- Three example of computer users are : (i) __________ (ii) ________
- Some of the jobs an operator uses the computer for are __________,
(ii) _____________ (iii) _______________
- A programmer is a person that repair computer. Tue or False
- A printer is an example of output devices. True or False
The means by which we communicate with the computer system are called input/output devices. The most commonly used in today’s computer system is the keyboard as described below.
At the end of this lesson, you should be able to:
(1) Identify and recognize the different sections that make up the keyboard.
(2) Recognize the location of the keys that make up each section.
Diagram of Keyboard
KEYBOARD: Computer keyboard is an input device which allows information to be communicated with the computer. It helps to enter responses to requests from the computer and enter commands that will require the computer to perform a task.
GROUP OF KEYS ON COMPUTER KEYBOARD
(i) FUNCTION KEY:
They are keys that can be programmed to perform functions which depend on software in use. They are the extreme left group of keys on the standard keyboard, but are the first line of keys on enhanced keyboard.
(ii) ALPHA NUMERIC KEYS:
These are the biggest groups of keys found at the centre of the keyboard. The alphabetic keys are arranged in the QWERTY as it is on the typewriter. The numeric keys are on the top rows of the alpha-numeric keypad and have the digits 0 – 9.
(iii) NUMERIC KEY PAD:
They can only function as numeric key, if numlock is on. They are arranged like a calculator for easy access. For both Standard and Enhanced keyboard, they are the extreme right group of keys.
- ARROW KEY: (CURSOR CONTROL KEYS):
They are called the direction keys, screen control or the navigational keys. On standard keyboard, they are the extreme right group of keys, while on the enhanced keyboard, they are of two sets. One set is between the alpha-numeric keypad and the extreme right group of keys. The other is the extreme right group of keys, some of the keys have arrows on them showing the direction to which the cursor would move when being tapped.
- SPACE BAR KEY:
This is the longest key on the computer keyboard. It is situated at the bottom of the alpha-numeric keypad. It creates blank characters which are used to separate words or characters.
- CAP LOCK KEY:
This changes alphabetic characters to upper case when on. It is usually located below the shift key on the left. Most keyboards have light that comes when caps lock is on. Turning caps lock on is simply a matter of tapping the key once.
(vii) ENTER OR RETURN KEY:
It returns the cursor to the beginning of a new line. However, each software are being used changes its use.
Return key is used to tell the computer that the input has finished and the computer should start processing the information.
- Mention two types of keyboard.
_________________ and _________________
- We use __________ device to fed in data and information to the computer.
- The Standard keyboard has _____ function keys
- the Enhanced keyboard has _____ function keys
- Another name for arrow key is ___________
- The longest key on the keyboard is ____________
- Another name for Enter Key is ___________
- The key that erases characters to the left of the cursor is ___________
- The key that can change lower case to upper case is called ________
- Mention four example of input devices from keyboard of
_________, __________, __________ and _____________
A mouse is an hand held digital input device that translate movement across a surface to cursor position on a usual display screen.
At the end of this lesson, you should be able to:
- identify the different parts of mouse,
- locate these parts on the mouse;
- use the mouse to perform:-
- Double click,
- Drag operations
Diagram of a mouse
- The mouse is a hand-held instrument connected to the system unit, which assists to carry out the commands in the computer.
- A mouse has a tract ball under, which enable the mouse pointer to move freely on the screen.
- The mouse is placed on a dust protective soft tissue called MOUSE PAD, this is to avoid dust from entering the mouse.
- Some mouse has two buttons, the left and right buttons, the left button is the most frequently used button on the screen.
- Besides other uses, the right button is used by the analysts for servicing on the control panel and other specified task.
FUNCTIONS OF MOUSE
- POINTING: The mouse point to an object to be selected. To point, move on a flat surface until the tip of the pointer is over the item or area you want to point.
- CLICKING: Pointing to an item on your screen and then quickly pressing and releasing the button is called clicking.
- DRAGGING: To move an object from one location to another. Press and hold down the left mouse button and point to where you want the object, then release the mouse button.
- DOUBLE CLICKING: Is the pressing and releasing of the left button of the mouse twice in rap succession.
The mouse is placed on a smooth surface tissue called Mouse Pad, which prevents dust from entering the mouse.
- The mouse is an ______ device.
- We place the mouse on the _____
- Some mouse has _____ buttons
- The mouse buttons are called __________ and ________ buttons
- The our functions of the mouse are: ____________, ____________,
_______________ and ___________
- To click means _______________
- To double click means _______________________
- The ball that regulates or control the mouse pointer is called _______
- A mouse is normally place on a smooth surface called _________
- Draw a mouse and labelled it.
Depending on how your computer is set up, various items appear on your screen when you start windows.
At the end of this lesson, you should be able to:
- Define desktop; state the functions of the desktop
- Identify the program icons on the desktop;
- Create and delete folders on the desktop;
- Use computer to explore files;
- Copy a file from one folder to another;
- Shut down windows
This is the first screen that appears when the computer system is ready for the user to start using it. The following are the components found in windows desktop also known as window starting screen.
- Task bar
- Start button
- My computer
- Recycle bin
This is the area on the screen that shows the various components of windows operating system, which can assume any colour or pattern at my time.
This is the pointing device that appears on the screen to show the corresponding movement of the mouse on the screen.
An icons is a pictorial representation of items on the screen, which could be a folder, or program depending on it appearance.
This is a bar at the bottom of the window that shows the name(s) of window that are opened; it also helps the user in switching between the programs since the names are being displayed.
You can click the start button on the task bar to start a program, open a document, change system settings, get Help, find items on your computer and so on.
When you double-click this icons you can see your computer’s content and manage your files.
The Recycle bin is a temporary storage place for deleted files. You can use it to retrieve files deleted in error or by mistake.
OPENING AND CLOSING PROGRAMS
Most of the program on your computer are available on a location such as PROGRAM section of the Start Menu. Depending on how your computer is configured, what you see on the start menu varies.
TO START A PROGRAM
- Click on the start button, and point to programs
- The programs menu appears
- Points to a group (such as accessories) that contains the program you want to start.
- Click the program name (such as paint).
TO CREATE FOLDERS
A folder is an icon that you can use to store a document.
- To create a folder, Right click on the desktop and select NEW
ii click on folder
iii. type the name to give e.g. KUFEE
- click on the Desktop
TO CREATE SHORTCUT
- Right-click on the desktop and select NEW
- click on shortcut
iii. type the location of the item
TO DELETE A FOLDER
- Right-click on the folder
- select DELETE
iii. click YES.
TO EXPLORE OR EXAMINE FILES
- Right-click on MY COMPUTER
- Click on EXPLORE
iii. Double-click on the icon representing the drive, file or folders
e.g. Drive C:/, Diskette (Floppy (Ai), CD Rom Drive (D) etc.
FUNCTIONS OF DESKTOP
The desktop is used for the following:-
- creating and deleting document
- Copying, renaming files from one directory to another
iii. Searching for files and document in the system
- Shutting down windows
- For setting up the system
TO QUITE A PROGRAM
Click the close button in the upper-right corner of the program window.
To turn off our electronic devices at home, we just press the ON/OFF switches. The way computer is turned off differs, some procedures are followed before computer is turn off. Shutting it down abnormally may get your software corrupted, and your hard disk damaged.
When you’ve finished working on your computer, you use the SHUT DOWN Command on the Start Menu to close window and programs and prepare your computer for shutting down. If you haven’t already save your work, you’re prompted to do so
TO SHUT DOWN A OCMPUTER
* Click on the Start button
* Start menus appear
* Click on Shut Down
* The Shut down windows dialog box appears
* Click on OK to turn off
* This message “It’s now safe to Turn Off Your Computer” will be displayed.
* Press the ON/OFF buttons on the monitor and system unit to turn it off
- The first screen that appear when you boot your computer is called __
- Mention five items that you can see on a window desktop _________,
____________, ___________, ___________, and ___________
- A pictorial representative of an item on the screen is called ________
- The button that can help the user to switch between program on the desktop is called _____________
- Mention three things that Start Button can be used for:
- A file that is mistakenly deleted from the computer can be recovered through _________________________
- To load a program called Microsoft word click on Start-button, point to program and select ______________
- Where is the Shut down Command found? _________________
- Mention 3 functions of Desktop.
(a) ___________, (b) _______________ (c) _______________
- If computer is not shut down properly, software may get corrupted . True or False
Computer games are special packages designed for children that can help them to developed their educational intelligence.
At the end of this lesson, you should be able to:
- Play the games;
- Predict actions of the key players;
- Suggest possible solutions to the any problems
Computer games are devices or computer programs that provides entertainment by challenging a person’s eye-hand coordination or mental abilities. It is made possible by the development of the micro-processor.
Electronic games or computer games are marketed in various formats, such as:
- Hand-held one-player models i.e. by the use of mouse or joystick.
- Cartridges or compact discs that are inserted in modules attached to television sets.
iii. Some of the program are displayed on the screen as in real life situation.
TYPES OF COMPUTER GAMES
There are many types of computer games developed by many vendors. Example of computer games are Nuts and Milk (J).nes, RUSNATK NES, GA (Aga (J) others are Prince, Test drive, Dave, Mario etc. these games are academically inclined adventure games. All these games help to developed the children learning skills such as addition, subtraction, multiplication and division.
The internet is a system of worldwide interconnection of computer networks for information interchange. There is need for you to learn more about this information super highway.
At the end of this lesson, you should be able to:
- Define the internet, worldwide web (www), electronic mail (e-mail), email address website.
- Internet browser
- e-mail address
iii. website address
- Access the internet; send and receive e-mail;
- Mention the benefits of internet
- Mention the abuses of internet
Internet MEANS International Network. This has made the world to become a global village. That mean people can communicate to one another easily, and information can transferred from one place to another in a very short period of time.
Every day, from home or office, millions of people use the internet. The internet is a network that connects computers world-wide. A network is a system whereby two or more computers are linked together by wires and other devices in order to share resources. Examples of resources shared are software, information, hardware devices like printers, etc.
We communicate in many ways:
- Face to face communication
- Communication through the telephone
- We use letters to communicate with ourselves
This internet allows communication between computers. In order to achieve this, computer networks world-wide need to be connected to the internet.
THE WORLD WIDE WEB (WWW)
The World Wide Web (www) usually called the web is global collection of multimedia documents and files, which are stored on computers connected to the internet.
WWW is a packages designed to present detailed information about an organization, products, services etc.
ELECTRONIC MAIL (E-MAIL)
Usually just called e-mail. This is a mode of communication which allows electronic exchange of message among users of the internet, through address called “E-mail Address”. E-mail addresses are found on the websites. There are some sites that render this service free. Some of them are:
Electronic mail is faster and convenient. Infact most computers at homes are used for it. Sometimes e-mail takes time to reach its destination. It could take ten minutes to reach, in some case, it takes hours.
This is a software programme that enables you to browse the world-wide-web. It makes sound, picture, animation and text to be received from the world-wide-web.
WRITING A FRESH MAIL OR COMPOSE E-MAIL MESSAGE
- Type in your ID (user identification) and password, then click on “sign in”.
- Move your mouse to “Compose” and click the left mouse button. (A window will appear on the screen in which you can compose a message).
- type in the topic or subject of the message you want to compose in the “subject field”.
- Enter the e-mail address of the recipient on the “to fold”.
- if you want other people to receive the carbon copy of the mail, then, type their e-mail address in “cc field”.
- Move your mouse to e-mail text window and click, then type the text you want to send.
- To send mail, move mouse pointer to send and click the left mouse button of the mouse once.
CHECKING AN E-MAIL
- Move the cursor to the “Address Field” and type in your web mail service e.g. http://www.yahoo.com.
- After loading move the mouse pointer to “E-Mail” and left click.
- Move the mouse pointer to “Existing User” and enter your users name in “User Name Field”
- Enter your password in the “Password Field”.
- Move to “Sign On” and left click, then, your mail box will open.
- Move to check mail and left click.
- To read mail, move mouse pointer to “Subject” of the mail to be read and left click.
After checking your mail, make sure you sign out completely to avoid other user access to your mail folder.
CHATTING (USE OF INTERNET)
One cannot get response from e-mail service instantly, also messages may take a very long time before getting to their destinations.
Chatting is an instant communication with an internet user anywhere in the world. People involved communicate (through texts) with each other at the same time, and feedbacks are got instantly.
BENEFITS OF INTERNET
- Quick and affective exchange of information.
- Recreation and entertainment.
- Access to data barks and research information
- Library services
- Access to experienced and export individuals
- Products or service advertisement
- File sharing and topic searching
- It provides access to almanac, dictionary, encyclopedias, and maps.
- It features exhaustive materials on the arts and employment opportunities.
DISADVANTAGES OF INTERNET
- It creates insecurity
- Theft and fraud is very common through internet
- Pornography i.e. naked picture of people
- It promotes corruption among youth.
- It promotes immorality when pornographic pictures are watched on the internet.
- INTERNET stands for _______
- Internet has turned the world to _____ village
- Example of resources shared by computer networking are ____, ____ and ___
- WWW stands for ___
- What is the full meaning of E-mail ______
- Instant communication, using text on the internet is called ___
- The process of search for information on the internet is called ___
- Three benefits of internet are:
- Two disadvantages of Internet are:
- Write three valid e-mail addresses
CARE OF COMPUTERS
Computer system environment is where computer system is placed. Proper planning of computer environment creates conducive atmosphere for computer hardware and enables the program (Software0 to run easily with minimal problems, if the computer is properly cared for.
At the end of this lesson, you should be able to:
- List ways of taking good care of a computer system
- Give reasons why computers should be taken care of
When planning computer system environment, the following should be noted:
- Air conditioning
- Burglary proofs
- Ceiling or standing fan
- Curtain materials
- Burglary light
- Carpet or rugged floor
- Tables and chairs.
The material or equipment in the computer system environment will depend on the type of micro computer installation being used.
Proper care must be given to the computer system to prevent physical damage, malfunction, loss of data and system failure. These could be achieved by proper positioning of the computer system and good maintenance.
COMPUTER ROOM EQUIPMENT
- Computer furniture or cabinets
- Micro computer
- Un-interruptible power supply (UPS)
- Electronic voltage stabilizer 9EVS)
- Cables, connectors and useful accessories.
- Protective devices
- Air-conditioning to control the temperature of the computer room from the installation ray
- Dust cleaner
METHODS OF ENSURING STAFF SAFETY AND EQUIPMENT SECURITY
- All the electrical connection should be adequately protected.
- Never remove the communication cables of peripherals attached to the CPU when the system is on.
- Use of stabilizer or UPS should be considered in computer room to guide against fluctuation in power supply
- Use the correct fuse rating
- The use of raised floor is needed to protect the system from water
- Always ensure the air conditioner is on for cooling effect
- Turn off your PC at the end of the day
- Turn off all the electrical appliances at the end of the day.
- The computer room should always be clean and tidy.
- The computer environment should be made of steel door and burglary.
STAGES IN CARING OF COMPUTERS
- CLEANING: cleaning can be done in two ways:
(i) Internal cleaning
(ii) External cleaning
- Internal cleaning: is carried out using system blower. The blower removes dust through blowing and sucking with the attached vacuum device. Also, diskette drive, cleaning kit can be used to clean the read/write head of floppy disk drives.
- External cleaning: On the external cleaning, swabs are used to remove dust and sticky substances from devices, keyboards and discharge wires on printers and scanners. The external chassis must be cleaned carefully with soap based, non abrasive, non-corrosive cleaning fluid. Also, user manuals can also be useful and helpful in cleaning peripherals.
- HARDWARE LEVEL: In this stage, the components must be carefully examined with the aim of checking for:
(i) Burning effects, which results from excessive heat being generated by the components.
(ii) The points of contacts and making sure such are connected.
(iii) The points of connection of data cables and power cables are to be cleaned with brushes and erasers.
(iv) Data cables and power cables connectors must be removed and reconnected.
(v) Mechanical parts can be lubricated where and when necessary. In doing this, the above steps are to be followed on the micro computer base unit, video display unit, keyboard, printers, power protecting devices and all necessary correction should be made where necessary.
REASONS FOR TAKING CARE OF COMPUTER:
- to avoid computer damages
- to protect the computer system
- To prolong the files of the computer system
- To make the user comfortable for maximum efficiency.
- Mention five things when planning computer system environment: They are: (i) _______ (ii) _______ (iii) _______ (iv) _____ (v) ____
- Five computer room equipment are: (i) _______ (ii) ________
(iii) ________ (iv) __________
- Stabilizer or UPS should be used to guide against ______
- The reason that the air-condition should be on is for _______
- The computer room should be kept clean and tidy, why? ______
- Two types of computer cleaning are: (a) _________ (b) ___________
- The type of cleaning that is carried out using system blower is called _
- Mention two reasons for caring for the computer.
- ____________________ (b) ________________________
- Mention three parts of the computer that must be handled carefully.
- __________________ (ii) ____________________
- Mechanical parts of the computer should be lubricated when necessary. True or False
BASIC PROGRAMMING LANGUAGE
BASIC is the acronym for Beginners All-purpose Symbolic Instruction Code. It is the name for programming language developed at Durtmonth College, New Hampshive, USA, under the direction of Professors John G. Kenenny and Thomas E. Kurtz, during their academic year between 1963 – 1964. BASIC was developed to teach beginners the construction of programming theory, and it is one of the easiest high level language to learn.
At the end of this lesson, you should be able to:
- Know why we learn Basic
- Code simple Basic Program
- Run a simple program
BASIC CHARACTER SET
A character denotes any letters, digit, punctuation, symbols or any other sign used in the representation of information in any language.
BASIC has the following character set:
(a) Alphabetic A, B, C, D – Z
(b) Number O, 1, 2 3, – 10
(c) Special Signs e.g.
^ Carret (Exponentiation operation)
* Asterick (Multiplication operation)
/ Slash (division)
+ Plus (addition)
( Left parenthesis
) Right parenthesis
$ Dolla Symbol
= Equality or assignment symbol
> Greater than
< Less than
“ “ Quotation mark
% Percent symbol
? Question mark
WHY LEARNING BASIC (ADVANTAGES)
The BASIC language is considered the most suitable for a first-level instruction to programming because:
- i) It is relatively easy to understand and quick to learn
- ii) It has a simplified grammar and relatively less number of statement.
iii) it is relatively easy to code.
- iv) It can be programmed on a terminal that is, it provides the students with an ability to interact directly with a computer.
- v) It is the most commonly used programming language for mini and micro computer system because of its small interpreter and compiler.
VERSION OF BASIC
After more than thirty years of it conception, more than 50 versions of BASIC have been developed for use on a variety of hardware system. All versions were standardized to conform with universally accepted standard, known as American National Standard (ANS). Systematic differences between versions of BASIC are often associated with hardware on which they are designed to be used. Some of the existing versions are:
- G W BASIC
- CASSETTE BASIC
- M F BASIC
- QUICK BASIC etc.
GETTING BASIC UNTO THE COMPUTER
Before programming can begin, the computer has to be switched on, and when the system program is displaced, the BASIC interpreter must be loaded into the computer memory, Type: C:> GW BASIC. The computer display “OK”, which means you are in BASIC directory. “OK” means the BASIC program is ready, that is, at the command level and it is ready to accept commands. At this point BASIC can be in either two modes. Direct mode or indirect mode.
The function keys (F1 – F10) assignments appears on the button line of the screen. These function keys can be used to eliminate key strokes and save your time.
SAVING YOUR PROGRAM FILE
Creating a program is like creating a data file. The program file contains specific instructions or statements for the computers. In order to use the program again, you must SAVE it, just as you would save a data file. To save a file in BASIC, use the following steps:
- Type “SAVE” or press the F4 key
- Type a name for the program and press the RETURN key ( ). The file is save under the name you specified.
TO RECALL A SAVE FILE
Use the following steps:
- Type LOAD or press the F3 key
- Type the name of the File
- Press Return ( ). The file is loaded into the memory and ready for use.
- Type list to see the content of your file.
Keywords are words that have special meaning to BASIC interpreter. These include all BASIC commands, statements, function, names and operator names, they cannot be used as variables names. They BASIC keywords are listed below:
- REM (ii) INPUT (iii) READ (iv) DATA (v) LET
- OR (vii) PRINT (viii) END (ix) STOP (x) GO
(xi) GOSUB (xii) FOR …NEXT (xiii) RETURN etc.
THE REM STATEMENT:
REM stands for Remark, they are not executable, but are output exactly as entered when the program is listed e.g. 10 REM program to Add two Numbers
This is used to feed numerical or strings data into the computer during program, execution. When the computer execute the input statements, a question mark (?) will be displayed on the console indicating a request for data.
20 INPUT A$
30 INPUT E, F. G
Where A$ is “My name is Kufre Etim” E, F. and G can be 100, 200, 300.
Print statement is used in BASIC language to print output data on the screen. As we have the INPUT statement, the print statement consists of a statement number keyword print and list of variable or instructions (expression). The punctuation used with PRINT statements determines the position of each printed items in the list.
In general, BASIC usually divides the times into zones of 14 spaces each e.g.
20 REM program to compute Average
30 INPUT A, B, C
40 LET Z = A + B + C
50 X = Z 3
60 PRINT “The Average = “ X
READ AND DATA STATEMENT
Read and Data statement are input statement i.e. Read statement is not used but used along with Data statement.
Read statement assign variable to Data statement values on a one-to-one basis. Read statement variable may be numeric or string, and the value Read must agree with the variable type specified.
The Read statement is used when the input have been stored in the computer memory, the storage of data is done by the Data statement. So, the use of both READ and DATA statement usually moves hand in hand with each other.
10 REM PROGRAM TO FIND THE PRODUCT OF THREE NUMBERS
20REA A, B, C
30 LET X = A* B8 C
40 PRINT X
50 DATA 4, 2, 5
- What do you understand by the acronym BASIC____________________
- _____ and _____ developed BASIC language
- BASIC was developed between _____ and _____ years.
- _____ is an example of BASIC character set.
- Mention three advantages of using BASIC language
- Two version of BASIC are ____- and _____
- Shortcut use in saving BASIC program is _____
- Five example of keyword used in BASIC ARE:
- READ statement is always accompanied with _____ statement.
- Write a program in BASIC to complete the area of a square i.e
Area + Length x Breathe
- Write a program in BASIC to calculate simple interest using the formula:
- Simple interest
- Determine the output of this program x and z
10 REM PROGRAM TO DETEMINE AVERAGE
20 READ A, B, C
30 LET X = A = B + C
40 Z = X/3
PRINT X= X
60 PRINT “THE AVERAGE = “Z
70 DATA 20, 10, 30
Operating system is a software or collection of programs that allow the computer and its peripheral to function. Operating system is very important to computer, without which computer will not work.
At the end of this lesson, you should be able to :
- Define operating system
- Types of operating system
- State the function of MS-dos
- State the feature of internal command with example
- Format diskette using ms-Dos
Operating system is defined as a set of instruction which initiates, activates and monitors the execution of other applications programs.
It controls the activities of the hardware components, while also acting as an interface between the users and the computer components.
TYPES OF OPERATING SYSTMEM
MS-DOS- Microsoft Disk Operating system
CPM – Control programmed for micro-computer.
PC-DOS- Personal computer DISK operating system for micro-computers
NOS- Networking operating system.
ZENX – A multi-user, multi-tasking operating system develop for UNIX, for super micro- computer.
AOS – Advanced operating system, window 95, windows 98, windows 2000
MS-DOS; Means Microsoft disk operating system.
FUNCTIONS OF MS-DOS:
- It simplifies the creation and management of files.
- DOS interprets any data input to the computer
- Dos is a house keeping tools that keep records of nay data stored on floppy disk or hard disk.
- It distributes information between the computer (CPU), monitor, keyboard and it peripherals e.g. printer, joystick and scanner.
- It provides commands for performing routine file maintenance such as deleting, re-name, formatting, copy etc.
- It allows the user to control the computer and other devices.
DOS command are valid instruction issued at Dos prompt to execute certain task or program.
These are commands issued to get things done on the computer.
There are two types of Dos command.
- Internal command
- External command
FEATURES OF INTERNAL COMMAND
- It is simple
- It is commonly used
- It resides in the computer memory
- Internal commands are part of command
EXAMPLES OF INTERNAL COMMAND
|COMMAND||SYBTAX (PATH NAME)|
|1||Directory||DIR, DIR/P, DIR/W|
- DIR COMMAND (DIRECTORY0)DIR allows a listing of all files and directories on the disk.
- It shows the size of each files.
- It shows the date and time a file was created
- It shows the time a file was last modified.
Practical use of DIR command
Step; at DOS prompt i.e. C:/>
Type :DIR 9then press Enter key)
DIR OPTIONS: DIR OPTIONS INCLUDE
(A). DIR/P: This shows the full columns of the total number of files an the remaining disk space will be displayed at once.
Steps: At C:/> type
- DIR/PP (press Enter key)
- DIR/W (press Enter key)
- DELETE COMMAND (DEL)
Delete command helps us to complete erase or remove a file from the disk. Delete command is useful when:
- There is limited memory space and you want to create more by removing some files.
- The file is no longer useful or needed.
Steps: at C;/> prompt type
Del & (drive) pathname (filename) e.g to remove all file with any 3 character as extension in drive A.
C:/> Del A: *??? (press Enter)
- COPY COMMAND
- Copy command allows duplicate of file.
- Copy command makes the transfer of information from one disk to another easier.
- Copy command adds to the number to the number of existing files on a disk.
Steps: At C:/.
Type: [copy & drive] [file name] press Enter
e.g. C:> copy kufre A: (this copy the file name kufre from drive C to A)
- RE-NAMING A FILE (REN)
This command allows you to change file name to another without changing anything in the file.
Step: At C:/.
Type: REN & (Drive name) (path) (file name 1 and file name 2) (press Enter)
This is used to clear information displayed on the monitor or screen.
Step: At C:/>
Type: CLS (press enter)
- VERSION (VER)
This displays the version of the operating system on a computer e.g. 4.1,5.1 etc.
At C:/>t type: Time (Press Enter)
- DATE: Displays current date and allows you to make changes if necessary
At C:/. Type: DATE 9pres enter
- MAKE DIRECTORY (MD)
This is used for creating a new directories
Type MD (file name or directory name) e.g.
MD John (press Enter)
- REMOVE DIRECTORY (RD0
Used to remove unwanted directories
Type RD John (press Enter)
MS-DOS stores external command on a disk and transfers them to computer memory when needed.
Examples of external command
- Disk copy
- Scan disk
- Check disk
- Format command allows us to get our disk ready for use, to give and receive information .
- Any information in the disk will be completely erased.
Type: Format (drive name:/b/s/v (press enter)
e.g. Format A: (press Enter)
- Disk cop y command copies the entire information from one disk to another.
- Disk copy makes an identical copy of the whole content.
At DOS prompt [C:/.]
Type: Disk copy & drive1; 7 Drive2:
N/B: Drive 1 is the source drive
Drive 2 is the target drive.
e.g C:/> Disk copy A:B; (press Enter)
SCAN DISK AND CHECK DISK
Scan the disk in the specified drive and check it for error. This command analyse the disk and gives additional information about the status of a disk.
At DOS PROMPT (C:/>)
TYPE: Chkdsk (Drive:) (IF) (IV) (press enter key0
Chdsk and scan disk command will supply the following information:
(a). The total number of space on disk
9b) The total space used
(c) The condition of the disk
(d) The total space available on the disk (unused space).
To quit DOS environment
At Dos prompt 9C;/>)
Type: Exit(press enter)
- What are operating system? …………………………………
- Are operating systems hardware or software?…………………………..
- Everything about a computer depends on it operating system (a) True (b) False
- List the types of operating systems we have ………………
- What type of operating system is on a computer used by one person?………
- The operating system on computers connected together is called…………………………………………………
- What are the function of the following command:
- DIR ……………………………………………….
- VER …………………………………………………….
- VOL ………………………………………………………….
- DEL …………………………………………………………
- TIME …………………………………………………………
- Five functions of operating system are
- Two features of internal command are
- Two examples of external command are: