Input and Output Devices

Input devices are computer equipment that we use to sends data into the computer. Without input devices, we cannot communicate with the computer. Some examples of input devices are:

Input Devices
  1. Keyboard
  2. Mouse
  3. Tracker ball
  4. Joystick
  5. Light pen
  6. Digital Camera
  7. Microphone
  8. Touch screen
  9. Video Digitizer
  10. Graphics tablet
  11. Scanner

Output Devices
Output devices are computer equipment that enables us to see the information processed by the computer. Output devices enable us to know what the computer is doing or has already done.
  1. Monitors or Visual Display Units (VDU's)
  2. Printers
  3. Plotters
Other devices

  1. Speakers
  2. LCD projectors

Computers and Data

Computers and Data
In order to understand data we need to process it. In other words, data must be taken through a number of processing stages in order to generate Information. Any technique in which data is retrieved, stored, classified, manipulated, transmitted and/or reported in such a way as to generate information; especially such processing using computers is called Data Processing.
Computers can perform all kinds of processing. From simple and complex calculations, classifications, arranging jumbled text alphabetically and vise versa as well as analyzing pictures and sounds.

Stages in Information Processing
Information is processed in three major stages. This is called the Information processing cycle.
In stage 1, data is collected from various sources. In stage 2, the data is processed by various computer techniques in order for it to make sense to us. The final output in stage 3 is what we call Information. Lastly, the computer stores the information in its memory.
How do Computers Process Information?
We feed the computer with Data using the keyboard and other Input devices. The data input is then sent to the System Unit where it is processed. After the data is processed, the system unit sends the Information to the Monitor or Printer to display what has been processed.

Take a close look at the illustration. It shows how data travels from the keyboard to the system unit, then to the monitor to be displayed.


Common Keyboard Symbols

The Keyboard

A keyboard is a rectangular computer equipment with buttons otherwise known as "keys". Each key represents the letter, symbol or number printed on it. It is an input device used for sending data to the computer.

Punctuation Marks

A simple paragraph may contain several punctuation marks. Punctuation marks are symbols used to clarify the content of a written material, i.e. separating words into sentences, clauses and phrases.
Punctuation keys can be found on a keyboard. If you look closely at your keyboard you will realize that there are two punctuation marks on a punctuation key.

Typing punctuation keys that do not involve the 

To type the punctuation mark at the bottom of the key, simply press the key. However, the Shift key is used when you want to type the punctuation mark located at the top of a punctuation key. In this lesson, you will learn how to type punctuation marks that do not involve the Shift key. Examples of these punctuation keys are the comma ( , ) the period 
( . ) the forward and back slash ( / \ ) and the semicolon ( ; ). 

Type the following punctuation keys.

Punctuation keys and their locations on a keyboard.
The Comma Key - The Comma key represents a pause. It is used to separate two words in a sentence. The Comma can be located at the right side of the letter M and is the third key to the left of the SHIFT key

The Full Stop - The Full stop expresses a halt or an end. The Full Stop can be located to the right of the comma key and is two keys to the left of the SHIFT key.

The Forward Slash - The Forward slash is used for separating optional items in a list or used to express a fraction or division. The forward Slash can be located to the immediate left of the SHIFT key.
The Back Slash - The Back slash is used for separating optional items in a list or used to express a fraction or division. The Back lash can be located above the enter key.

The Semicolon - The Semi-Colon is used for separating two parts of a sentence that have a relationship to each other but can otherwise stand alone. The semicolon can be located to the right of the letter L and is two keys to the left of the ENTER key.
Page | 8.2 - Using the paragraph below as a guide, type the paragraph into the space provided in the e-Student CD-ROM. 

Type this: 
The leader of Ghana, Kwame Nkrumah, was overthrown by a military coup in 1966. It has been argued that this was supported by the U.S. Central Intelligence Agency; that assertion remains generally unproven. A series of subsequent coups ended with the ascension to power of Flight Lieutenant Jerry Rawlings in 1981. These changes resulted in the suspension of the constitution in 1981 and the banning of political parties. A new constitution, restoring multi-party politics, was promulgated in 1992, and Rawlings was elected as president in the free and fair elections of that year and again won the elections 1996 to serve his second term. The constitution prohibited him from running for a third term. 2007 marked Ghana's Golden Jubilee, celebrating fifty years of independence since 6 March 1957. In 2009 John Atta Mills took office as president, the second time power in the country had been transferred from one legitimately elected leader to another, securing Ghana's status as a stable democracy.

Learning with ICT Tools

Learning with ICT Tools
How computers are used to support learning.
Information and Communication Tools are equipments that are used to process data into information. They are also used for sending and receiving information. Some ICT tools are Computers, Mobile Phones, Radio and Television etc.
In recent years, ICT has turned from being a technology of communication and information to a tool for curriculum creation that supports teaching and learning.
Computers can be used in the classroom. They can help teachers to keep records of lessons and grades of all students in their class. Students can also use computers to study and do research through educational software or the World Wide Web.
Accessing Information
When students want to look for information they can use the Internet. The Internet is the largest network of computers and has a large amount of educational Information. By using search engines like Google, students can easily find articles and publications that are related to their field of study. For example, to find a particular book, go to
The Television / Radio can be used to transmit educational programs for us to watch /listen in our homes. Some educational programs we can watch/listen are programs such as health and safety on HIV or other health issues.
Sharing Idea's
Students can also share ideas using ICT tools. They can create discussion forums on the Internet where they can share thoughts concerning some important issues. Students can share information via emails or on the local network in their school's computer lab. They can also do their homework using the telephone or an online instant messenger. ICT tools are very useful for sharing ideas.
We no longer need to use our fingers to do complex calculations. Computers are the fastest tools we can use for calculations. Students who study complex mathematical problems can conveniently use the computer to solve them. The scientific calculator is a good tool for science and math students in the secondary and tertiary schools. Nowadays mobile phones have calculators on them.
Illustrations help to make studying more efficient because students are able to see what the teacher is really talking about. Presenting pictures, video and audio items help the students to get a clearer picture and experience what the teacher is talking about for themselves. Computers can help a teacher to share music, videos and pictures with students when teaching. This makes teaching and learning more effective.

Introduction to Manipulative Keys

Introduction to Manipulative keys
Keys with multiple functions
On a Standard and Enhanced keyboard, there are keys that have more than one function. There are other keys that have been assigned to perform special functions. Such keys are known as manipulative keys. For example, the delete key is used to erase errors made when typing a text or clear unwanted files from the computers memory. It is also used in combination with the Alt key and the Ctrl key when you want to restart the computer.

Let's take a look at some manipulative keys.
Shift Key.
The Shift key is a modifier key on a keyboard; it is used to type capital letters and other alternate "upper" characters. There are two shift keys on the keyboard. One on the left (below the caps Lock key) and right sides (below the enter key).
Tab Key.
The Tab key on a keyboard is used to move the cursor to the next "tab stop". Tab is the abbreviation for Tabulator. To tabulate, (tabulating) means to put something into a table or chart.

Backspace Key.
Backspace key moves the cursor backward one character space. It can also be used to delete the character to the left of the cursor. It is particularly useful for correcting spelling mistakes.

Enter Key.
The enter key is also known as the Return key, it is used to move a cursor to the next line or execute a command or operation. You can find two enter keys on most keyboards, one on the main key pad and another on the numerical keypad.

Insert Key.
Sometimes displayed as INS on the keyboard, the Insert key is a key allows text to be inserted. When insert is enabled, it allows text to be typed over existing text in a document.

Delete Key
On computer keyboards, the delete key (sometimes shortened "DEL"), normally erases the character at the cursor's position, moving all following characters one position "back" towards the freed place.

Health and Safety Using ICT Tools

Health and Safety using ICT Tools.
Uses of ICT Tools
Information and Communicating Technology (ICT) tools are computer-based equipment used for processing data and communication. Some ICT tools are

  1. Television
  2. Public Address System
  3. Radio
  4. Mobile Phone
  5. Computer

ICT tools are very useful in many other ways. We watch television programs for entertainment, education and information. The Public Address System is used for making community announcements by amplifying the voice of the user. The radio presents programs, music and discussions that keep us informed and entertained. The Mobile phone helps us to stay in touch with our friends, family and colleagues and finally the computer enables us to surf the Internet and communicate with other people online, it is also a form of entertainment because we can use it to watch movies and listen to music as well. Computers can also be used in businesses for communicating, desktop publication, sound editing.
Although it is unlikely that using ICT equipment will be dangerous in itself, it can be used in ways which can be a hazard to our health. In this lesson you will learn about the possible long-term health hazards associated with the use of ICT equipment and ways to avoid these health problems.
It is important to note that although ICT makes our lives easier, long term exposure to ICT equipment without precaution may lead to possible health hazards in future. Here are some of the possible health hazards.

Safety precautions for the use of ICT Tools.

What are the negative effects of long term exposure to television?
Your eyes are not suited for staring into the television set for hours. Staring into the television set for hours can be dangerous and harmful to the eye. By staring continuously you cause the eye to overwork itself and this may lead to eye irritation, such as dry eye, red, itchy, and watery eyes, fatigue, including heaviness of the eyelids or forehead; and difficulty in focusing the eyes.
Negative effects of improperly using the Computer.
Eye irritation and Eye fatigue.
The negative effects of using a computer do not differ greatly from that of the television. Staring at the monitor for more than two hours a day can lead to eye irritation, such as watery eyes, heaviness of the eyelids or forehead, difficulty in focusing the eyes and fatigue of the eye structures etc. It is therefore important to keep a distance of 20 to 26 inches away from the monitor and arrange your lights sources in order to prevent reflections or glare on the monitor screen.
Lower Back Pain
Sitting behind the computer for long periods or using the wrong kind of chair can also lead to problems in the future. It can lead to pain in the lumbar region of the back.
Wrist Pain
People may also experience wrist pains usually because their hands are not positioned properly when typing. Pains in the back, wrists or fingers often occur when you are not able to reach the keyboard and mouse whilst bending your elbows at 90 degrees, with your shoulders relaxed.
Cold and Flu
People who work for many hours in air-conditioned rooms may suffer from cold and flu.
Mobile phones and our Health.

It is believed that mobile phones can affect the health of people who use them. Research from Finland suggests that mobile phone radiation causes changes in the brain and even low level emissions from headsets are still damaging. However, there has not been any major research that provides scientific evidence of the danger of using mobile phones. It is therefore too soon to reach a definitive verdict on health risk from mobile phones. Nevertheless there are some effects that you can have when you do not use the mobile phone properly.

Some of the long-term health effects are:
1. Headaches and tiredness.
Using the mobile phone for hours can be very stressful and may lead to mild or severe headaches.

2. Creates joint pain.
Holding the mobile phone to your ear for more than 15 minutes can lead to a strain of your wrist and ligaments in the back of the hand.

3. Mobile phone battery explosion.
It is not advisable to use your mobile phone whilst charging it. Sometimes mobile phone batteries over heat and explode in such cases. You can be seriously injured if this happens to you.

4. Induced ringing! In the ears.
You can overwork your ear-drum when you hold the mobile phone very close to your ear. Keeping the mobile phone close to your ear for long periods of time may weaken your eardrums, induce ringing in your ears and eventually damage your hearing abilities in future.
Some negative effects of listening to loud sounds from the radio.

The radio is an interesting source of information and entertainment. Nowadays radio's come in handy. The pocket radio is widely used in Ghana. You can find people walking around with the radio's sets or headphones in their ears. Some people enjoy it when their radio volume is turned up to the highest level. Although this seems very entertaining, it is dangerous to your health because loud sounds tend to weaken your eardrums which may affect your hearing in future.

Public Address Systems

Loud sounds from Public Address Systems are also harmful to the human ear. Loud and prolonged sounds emitted from this equipment can cause hearing loss in the long run.

Opening Applications

Opening Applications
Application software is made to perform a specific task for the user. In this lesson you will learn how to open such applications on the Computer.
  To open an application,
1. Click on the Start Menu
2. From the Start menu select All Programs.
3. Click on the Application you want to open and wait for it to load on the screen.

1. Click on the Start Menu C:\Main\Webpages\yr1\illa.jpg

2. Select All Programs


3. Select the Application you wish to launch


Turning the Computer On and Off

Turning the Computer ON or OFF
Turning the Computer ON
The computer is electronic equipment - meaning it uses electricity. Electricity can be harmful if we don't work safely when using the computer. There is a basic procedure you must follow when turning the computer ON. If you want your computer to last long and work efficiently, you must always follow this procedure.

    Steps you are to follow when turning the computer ON.
  1. Check all the cables connected to your computer. These wires carry electricity. So be careful when doing so. Make sure they are all well-connected.
  2. Check the main socket cable and switch. Make sure the plug is connected well before you turn the switch on.
  3. Make sure you remove all pen drives, removable hard disks, diskettes and any other removable storage device from the computer before turning it ON
  4. Press the Power button of the System unit and the Monitor. Note: These may be located at different parts on different personal computers

Here are some reasons why your computer may not work.
  1. If your plug has a fuse in it and the fuse is burnt, your computer will not start. Call an electrician to check the fuse and replace it if it is indeed burnt.
  2. All computers are not the same. Different computers can be switched ON in different ways. Some have the power switch at the front or back whilst others have the switch at the side.
  3. If your computer comes with a manual, it is advisable to read it before you peel the plastic from your brand new computer. Most manuals have troubleshooting tips that could help you further, with specific instructions for your machine.

    Turning the Computer OFF
After using the computer it is also important to turn it off in other words, to "shut the computer down." The process is simple.
Shutting the Computer down
1. Make sure all applications running on the computer are closed.
2. Click on the Start Menu.
3. Click on Turn Off Computer.
4. Select Turn Off from the dialogue box and wait patiently for the screen to go off.
5. Turn off the Monitor.
6. Switch off the main socket.
1. Make sure all applications are closed.

2. Click on the Start Menu


3. Click on Turn off Computer


4. Select TURN OFF


5. Wait patiently for the screen to go off.

6. Turn off the Monitor.

7. Switch off the main socket.

Note: Some system units automatically go off with the shutdown command. Pressing on the power button after shutdown will only restart the computer.

Input and Output Devices

Input devices are computer equipment that we use to sends data into the computer. Without input devices, we cannot communicate with the comp...