1. Input device:
The equipment of the computer, which is use to give data to the computer is called input device. For example: keyboard, mouse, scanner, digital camera etc.
Key board
This is an input device, which is connected with the CPU. It is use to give data to the computer. Key board is an essential input device. The longest key of the key board is space bar, which is followed by thumb. F1 to F12 are function keys, which can be found at the top of the key board. ESC key can be found at the top left of the keyboard, which is use to cancel different comma and or program. we get alphabets, at the middle cursor control key and at the right part we get numeric key pad. Normally more than 104 keys can be found in the key board. Ctrl, Alt, Shift, Enter & Start the keys, which can be found at the two places of the key board.
Mouse
This is an input device, which is connected with the CPU. It is use to give instruction to the computer. Mouse makes easy to operate windows base program. Some mouse has only one key, some has two and some mouse has three keys also to click.
Light Pen
This is an input de vice, which is connected with the CPU. It is use to directly touch in the screen. It has on/off switch as well as its nib is very soft. Especially this equipment is use by engineer, overseer, architecture, graphics designer & others.
Scanner
This is an input device, which is connected with the CPU. It is use to transfer graphics data (photo) to the computer. The function of scanner is same with phot o copy machine but it is small in size.
Micro Phone
This is an input device, which is connected with the CPU. It is use to record our voice in the computer as well as to communicate with the people taking help with Internet.
Digital Camera
This is an input device, which is connected with the CPU. It is use to take photograph in the computer. Digital camera can be disconnected with the CPU because it has memory card. Using USB cable, we can transfer photo from camera to computer.
Web Camera
This is an input device, which is connected with the CPU. It is use to send video to the next internet user. We can record video and take photos but the quality is too low
2. CPU (Central Processing Unit)
It stands for central processing unit. It is also known as brain of the computer. All input & output devices are connected with the CPU. Without connecting with CPU, they can’t work properly. There are 3 units in the CPU. They are control unit, Arithmetic & Logic unit and memory unit.
A. CU (Control Unit)
It stands for control unit. It controls all the operation of the computer. It controls computer hardware & software too It gets data from input device. It checks the data. If the data is mathematical or logical it sends to ALU, otherwise it directly sends to the MU. When ALU returns data to CU, it sends to MU. After all, when memory unit returns data to the control unit, then it sends to output device.
B. ALU (Arithmetic & Logical Unit)
It stands for Arithmetic & Logic unit. The function of this unit is to perform mathematical and logical works. It gets data from control unit and returns to control unit after completing task.
C. MU (Memory Unit)
It stands for memory u nit. The function of this unit it to store data in the primary memory. It gets data from control unit and returns to control unit after saving data in the primary memory.
Note that, Charles Babbage is known as the father of Computer.
3. Output device:
The equipment of the computer, which is use to get report from the computer is called output device.
For example: - Monitor, Speaker, and Printer etc.
Monitor
This is an output device, which is connected with the CPU. It is use to get visual report in the screen.
Monitor has on/off switch as well as color management switch too. Color & B/W both type of monitor can be found in the market. Monitor is also known as VDU, CRT, Screen & others.
Printer
This is an output device, which is connected with the CPU. It is use to get printed result in the paper. Printer itself has on/off switch as well as paper management switch too.
Speaker
This is an output device, which is connected with the CPU. It is use to get sound in high volume. Speaker itself has on/off switch as well as volume control switch too.
4. Memory Device:
Computer use memory to hold the programs and data in use by the CPU. Most computers have several type of memory. The main propose of the memory is to store program and data. There are two general categories of memory.
