Basic Computer Organization.

 Hey, learners today we are going to learn "Basic Computer Organisation". The shape,size, perforamance and cost of computers is changing fastly every year, but even after that the computer systems perform the following five operations for converting raw data into useful information and presenting it to a user.

The five operations are:-

1. Inputting

2. Storing

3. Processing

4. Outputting

5. Controlling

Let's discuss this topic in brief.

1. Inputting:- 

It is the process of intering data and instructions into a computer system.

2. Storing:-

As the name given, this process helps in saving data and instructions to make them readly available for initial or additional processing as and when required.

3. Processing:-

In this process any computer device, Performing arithmetic operations or logical operations on data to convert them into useful information.

4. Outputting:-

It is the process of producing useful information or results for a user, such as printed report or visual display.

5. Controlling:-

Directing the manner and sequence in which the above operations are performed.

My main motive to discuss about this topic is, to familiarize you with the units of a computer system.

Must keep in mind that the internal archiecture of computers differs from one system model to another.

But the basic organization remains the same for all computer systems.

*Input Unit:-

In short input units perform following functions:-

It accepts instructions and data in computer acceptable form.

It converts these instructions and data in computer acceptable form.

It supplies the converted instructions and data to computer system for further processing.

*Output Unit:-

In short Output units performed following functions:-

It accepts the results produced by a computer, which are in coded form and hence, we cannot easily understand them.

It converts these coded results to human acceptable form.

It supplies the converted results to outside world.

*Storage Unit:-

In short, a storage unit stores:-

Data and instructions required for processing (received from input devices).

Intermediate results of processing.

Results for output, before they are released to an output device.

Storage unit is divided into two categories:-

1. Primary Storage:-

Primary storage of a computer, also known as its main memory, it is used to hold pieces of program instructions and data, intermediate results of processing and recently produced results of those job on which the computer is currently working.

Primary storage normally has limited storage capacity because it is very expensive.

Primary storage of modern computer systems is made of semiconductor devices.

2. Secondary storage:-

Secondary storage of a computer also known as its auxiliary storage, is used to take care of the limitations of primary storage.

Secondary storage is much cheaper than primary storage and it can retain information even when a computer system switches off or resets. This storage also holds the program instructions, data, and information.

Magnetic disk is the most commonly used storage medium.

3. Arithmetic logical unit (ALU):-

ALU is a place in computer system where actual execution of instructions take place during processing operation. Calculations and all comparisons are made by ALU. Data and instructions stored in primary storage before processing are transferred when nedded to the ALU where processing takes place.

ALUs are designed to perform the four basic arithmetic operations (add, subtract, multiply and divide) and logical operations or comparisons such as, less than, equal to and greater than.

4. Control Unit:-

It manages and coordinates the entire computer system. It obtains instructions from the program stored in main memory, interprets the instructions, and issues signals causing other units of the system to execute them.

5. Central Processing Unit:-

Control Unit (CU) and Arithmetic logic unit (ALU) of a system together known as the Central Processing Unit (CPU). Basically CPU is known as the brain of computer, all major calculations and comparisons take place inside the CPU and the CPU is responsible for activating and controlling the operations of other units of the computer system.

6. The System Concept:-

A system is a group of integrated parts that have a common purpose of achieving some objective(s).

Any system must have the following three characteristics:

(a) It must have a more than one element.

(b) All its element must be related logically.

(c) All its element must be controlled in a manner to achieve the system goal.

In any system the usefulness of each unit depends on other units and is realizable only when all units are put together to form a system.