Units of a typical computer

Every computer has a certain architecture. It consists of various components. The basic function of this component is to interconnected to form a specific system. The given figure explain the basic structure of a computers.

There are three main basic units in a typical computer are as follow:-----

1. 1.Input unit.
2. 2.System unit.
3. 3.Output Unit.

Input Device

It is a kind of device that is connected to CPU(Central Processing Unit).This device is used to give all instructions and command to the computer for performing different kind of activity.There is a Control unit that take all the command and instruction from a user and send it to the CPU where it is processed as situation needs. Keyboard is the most common Input Unit. Other Input Units are as follow :-----

1. 1.Mouse
2. 2.Light Pen
3. 3.Trackball
4. 4.Disks
5. 5.Joystick
6. 6.Scanner
7. 7.Microphone

System unit

System unit is a place where all the command and data are store and processed after receiving all data from some input device. It consists of two parts are as follow:-----

1. 1.Central Processing Unit
2. 2.Memory Unit

Central Processing Unit

It is also known as CPU. It is a place where all the data and instruction are processed. For this reason it is also known as the brain and heart of a computer system. It is divided into two basic units these are:------

1. 1.Control Unit
2. 2.Logic and Arithmetic Unit

This is a very important unit as in the respect of function. It function is to control and Coordinates the total activities of all the parts and units of a computer system. There is a list of some of the function perform by Control unit are as follow------

1. 1.It brings all the instruction, Command and data from main memory.
2. 2.Interpret all type of instruction.
3. 3.It controls the movement of data from the main memory and into the main memory.
4. 4.Input and Output device is also control by Control unit.
5. 5.It is responsible for whole management of a computer system.

Logic and Arithmetic unit

All arithmetic calculation like addition , subtraction , multiplication and division are perform in this unit. It unit is also known as ALU. A typical ALU Consist of a part that is electronic circuitry and by this ALU perform all type of arithmetic calculation. For logical operation it has a Logic circuitry. It give result in two form whether TRUE or FALSE. It receives all the necessary command from the Control unit to perform all the operation that is discuss earlier.

Memory Unit

This unit is also known as storage device as name suggested. It is a place where all the data and instruction are store that are given by user side. Computer use Bytes , Bits and words to measure the memory of a computer .A Bit is represented as 0 or 1. 0 or 1 is a binary digit. A Byte is a type of sequence and is always measure in a sequence of 8 and word is measure in a sequence of 16 bits or 2 bytes.

The memory of a computer is divided into three parts are as follow:-----

1. 1.Main Memory
2. 2.Cache memory
3. 3.Secondary memory

Main memory

Main memory is a place that store all the data received through the input devices. The storage is temporary and all the data are erased when we switched off the power and that why it is known as a primary memory.

The capacity in the term of storage is measured in megabytes and gigabytes. The two most commonly primary memory is RAM Or ROM

Secondary Memory

Secondary memory is also known as a permanent memory. The capacity is very high as it store a large amount of data for a longer period of time. This memory is connected to the CPU. Magnetic material is used to made a Secondary memory. Some of the well known secondary memory are as follow -----

1. 1.Magnetic Disk
2. 2.Magnetic tape
3. 3.Magnetic Drum

Cache Memory

This type of memory is placed in between the CPU and the main memory. We can access all the data at a higher speed when we compare to a main memory. The user like us are not able to access this type of memory. During the execution of any program the data and instruction are stored in that memory.

Output Unit

This unit is used to display a result which is obtain after the execution of any program or instruction that we feed it to computer with the help of Input device. The most commonly output device is monitor. Other Output devices are as follow --------

1. 1.Printer
2. 2.Plasma Display
3. 3.Plotter
4. 4.LCD display
5. 5.Speaker
6. 6.Disks
7. 7.Printers