The computer systems contain three components: the central processing unit, input devices, and output devices as seen under the following image.
The input devices supply a processor with data input, which processes the data and produces valuable information, shown by output devices to the user.
Stored in the memory of a machine.
Central Processing Unit
The Central Processing Unit (CPU) is called “the brain of the computer” as it controls the operation of all parts of the computer. It consists of two components: Arithmetic Logic Unit (ALU), and Control Unit.
Arithmetic Logic Unit (ALU)
Data entered into the computer is sent to RAM, from where it is then sent to ALU, where the rest of the data processing takes place.
All types of processing, such as comparisons, decision-making, and processing of non-numeric information takes place here, and once again data is moved to RAM.
Control Unit
As the name indicates, this part of the CPU extracts instructions, performs execution, maintains, and directs operations of the entire system.
Functions of Control Unit
- Control unit performs the following functions −
- It controls all activities of the computer
- Supervises flow of data within CPU
- Directs the flow of data within the CPU
- Transfers data to Arithmetic and Logic Unit
- Transfers results to memory
- Fetches results from memory to output devices
Memory Unit
This is a unit in which data and instructions given to the computer as well as results are given by computers are stored. The unit of memory is “Byte”.
1 Byte = 8 Bits
What is a Computer?
A computer is an electronic device that accepts data from the user, processes it, produces results, displays them to the users, and stores the results for future usage.
Data is a collection of unorganized facts & figures and does not provide any further information regarding patterns, context, etc. Hence data means “unstructured facts and figures”.
Information is structured data i.e. organized meaningful and processed data. To process the data and convert it into information, a computer is used.
Functions of Computers
A computer performs the following functions:
Receiving Input
Data is fed into the computer through various input devices like keyboard, mouse, digital pens, etc. Input can also be fed through devices like CD-ROM, pen drive, scanner, etc.
Processing the information
Operations on the input data are carried out based on the instructions provided in the programs.
Storing the information
After processing, the information gets stored in the primary or secondary storage area.
Producing output
The processed information and other details are communicated to the outside world through output devices like monitor, printer, etc.
| · History of Computers
The history of the computer dates back to several years. There are five prominent generations of computers. Each generation has witnessed several technological advances that change the functionality of the computers. |
| · Characteristics of Computer System
Characteristics of Computer Systems involve Speed, Accuracy, Diligence, Versatility, Reliability, Automation, Memory. |
| · Basic Applications of Computer
Computers play a role in every field of life. They are used in homes, businesses, educational institutions, research organizations, medical field, government offices, entertainment, etc. |
| · Components of Computer System
Computer systems consist of three components as shown in the below image: Central Processing Unit, Input devices, and Output devices. |
| · Input Devices – Keyboard and Mouse
Input devices help to get input or data from the user. |
| · Other Input Devices
Few other input devices help to feed data to the computer. |
| · Output Devices
Output devices help to display output to the user |
| · Computer Memory
Computer memory refers to the storage area where data is stored. It is of two types Primary Memory & Secondary Memory. |
| · Concept of Hardware and Software
The term hardware refers to a mechanical device that makes up a computer. The software can be categorized into two types – System software & Application software |
| · Programming Languages The languages that are used to write a program or set of instructions are called “Programming languages”. Programming languages are broadly categorized into three types – Machine level language, Assembly level language, High-level language. |