In our previous chapter, we have learned about data and instructions. Data is essential, without which the computer cannot work.
A user working on a computer enters the data through the input devices, and the processed data can be seen on the output device.
Let us learn in detail about these devices.
Input Devices
The device used to enter data into the computer is called the input device.
Some of the most common types of input devices are as follows:
Keyboard
- This device is used to enter data into the computer.
- The keyboard is similar to a typewriter keyboard.
- The keyboard generally consists of 101 keys.
The keyboard is connected to a computer with a wire. It has many keys with symbols on it, which work differently.
The table given below provides the list of keys present in the keyboard, along with their functions.
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Keys |
Functions |
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Letter keys |
These keys are used to type |
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Small letters (a-z) |
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Capital letters (A-Z) |
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Numbers (0, 1, 2, 3…) |
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Punctuation symbols ([], . / : “” ;…) |
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Caps lock key |
This key is used to type capital or small letters. |
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When the caps lock key is pressed, it helps write capital letters. |
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The letters are typed in lower cases or small letters when it is not pressed. |
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Function keys |
Function keys are used to give specific commands to computers. |
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There are 12 function keys on the keyboard, F1 to F12. |
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Shift key |
When a key has two symbols, keep the shift key pressed and press that symbol key to type the upper symbol. |
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The shift key is also used to type capital letters. |
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Spacebar key |
The spacebar key is the most extended key on the keyboard. |
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It is used to give space wherever required. |
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Backspace key |
The backspace key is used to erase the letters from right to left. |
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Delete key |
The delete key is used to delete the letter on the right side of the cursor. |
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Arrow keys |
Arrow keys are used to move the cursor on all four sides. |
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There are four arrow keys (← ↑ → ↓). |
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Enter or Return key |
Enter key is used to: |
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Enter the data. |
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Start a new paragraph. |
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Send instructions to the CPU. |
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Move to the following line of the paragraph. |
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Numeric keypad |
This is on the right side of the keyboard. |
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These are from 0 to 9. |
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Some of its keys have dual functions. |
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When num lock is on, these keys work as number keys. |
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When num lock is off, these keys work as the symbols written on them. |
Mouse
A mouse is a small device that can be moved in different directions on the surface of a table with the help of a hand. This device is connected to a computer with a wire. When a mouse is moved on the surface of a table, an arrow sign on a screen is seen, which can be moved in all directions. This arrow sign is called a mouse pointer.
How to operate a mouse?
- A mouse is a multipurpose tool, which is used in various tasks.
- It helps to make pictures and is moved on a mouse pad.
- A mouse has two or three buttons, which are clicked or pressed with fingers.
Clicking
- Mouse pointers can be dragged to an icon on a monitor.
- When the mouse’s left button is pressed, it is called clicking.
- When the mouse’s right button is pressed, it is called right-clicking.
- Clicking is used to select a file or any icon- When the mouse clicks on any file or any icon only once on the desktop, that icon gets selected.
Double-clicking
- When the mouse’s left button is pressed or clicked twice, it is called double-clicking.
- Double-clicking is used to open a file and start the program.
Microphone
A microphone is an input device used to send music files or audio into the computer.
Scanner
The scanner is an input device used to send photographs, printed files, or other documents to the computer.
Other input devices used to enter data into a computer include Joystick, Light pen, Trackball, Webcam, etc.
Output Devices
This unit is used to receive the processed data. A user can view the output data on a monitor, and the obtained result can also be printed with the help of a printer. The printer is an example of an output device.
Some of the most common types of output devices are as follows:
Monitor
- The monitor is an output device that looks similar to a television.
- This device is connected to a computer with a wire.
- With the help of this device, a user can see the input data or the instructions on the monitor, which a user enters along with the result of the processed data.
Printer
- Printers are an essential accessory of the computer.
- This device is connected to a computer with a wire.
- With the help of this output device, a user can print the processed data and other stored data from the computer on paper.
There are different types of printers. The most commonly used are:
1. Dot Matrix Printer
2. Inkjet Printer
3. Laser Printer
Other output devices used to receive the processed data from computers include Plotter, Speaker, etc.
Storage Devices
The device used to store the data is called a storage device.
The storage devices are of two types:
Primary Devices
- This is a fixed storage device in a computer.
- It has RAM – Random Access Memory and ROM – Read-Only Memory.
- RAM stores temporary data. If the power goes off, data is lost.
Secondary Devices
- They are external devices used to store data and information for a more extended time.
- These devices are used to store the data permanently.
- These devices are used in need and are easy to carry anywhere.
- CD, Hard disks, pen drives, memory cards, etc., are examples of secondary devices.
Frequently Asked Questions
Which keys in the keyboard give specific commands to the computer?
Function keys are used to give specific commands to the computer. There are 12 function keys – F1 to F12.
What is a Hard Disk?
A hard disk is a magnetic device, which stores all the information or the work done on a computer.
What is the full form of RAM and ROM?
The full form of RAM is Random Access Memory
The full form of ROM is Read-Only Memory
Which is the smallest unit of data in a computer?
The bit is the smallest unit of data in a computer.
What is DVD.?
DVD or Digital Versatile Disc has higher storage capacity than the CD. We can use DVDs to read as well as write data.
How many bytes are needed to make one kilobyte?
1024 bytes are needed to make one kilobyte.
Why is the Caps lock key in the keyboard used?
The Caps lock key in the keyboard is used to type both the letters (capital or small letters)
What is a pen drive?
A pen drive is a USB device, which is inserted into a computer’s USB port. The size of this USB device is small and can store a large amount of data in it. This device can be carried and used by inserting it into other computer devices.
Stay tuned to BYJU’S for more information on NIOS, syllabus, notes, along with its important questions and solutions.
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