What is a Computer?

In my way the definition of computer will be

In this world, four properties are match in anything, that is called a computer.
1) Electronic Device
2) Take Input
3) Processing
4) Give Output

What is Computer?

Computer is an advanced electronic device that takes raw data as input from the user and processes these data under the control of set of instructions (called program) and gives the result (output) and saves output for the future use. It can process both numerical and non-numerical (arithmetic and logical) calculations. 

A computer has four functions:

1. accepts data
2. processes data
3. produces data
4. stores result

      INPUT DATA :

    Input is the raw information entered into a computer from the input devices. It is the collection of letters, numbers, images etc. 

   PROCESS :

        Process is the operation of data as per given instruction. It is totally internal process of the computer system.

OUTPUT :

Output is the processed data given by computer after data processing. Output is also called as Result. We can save these results in the storage devices for the future use. 

Computer System

All of the components of a computer system can be summarized with the simple equations.
COMPUTER SYSTEM = HARDWARE + SOFTWARE+ USER

• HARDWARE=Internal devices + Peripheral devices

         All physical parts of the computer (or every thing which is tangible) are known as Hardware.

• SOFTWARE = Programs

       Software gives "intelligence" to the computer.

• USER = A person who operates computer.

Generation of Computer:

First Generation(1940-1956):

The first generation computers used vaccum tubes & machine language was used for giving the instructions. These computer were large in size & their programming was difficult task. The electricity consumption was very high. Some computers of this generation are ENIAC, EDVAC, EDSAC & UNIVAC-1.

Second Generation (1956-1963):

In second generation computers, vaccum tubes were replaced by transistors. They required only 1/10 of power required by tubes. This generation computers generated less heat & were reliable. The first operating system developed in this generation. 

Third Generation (1964-1971):

The third generation computers replaced transistors with Integrated circuit known as chip. From Small scale integrated circuits which had 10 transistors per chip, technology developed to MSI circuits with 100 transistors per chip. These computers were smaller, faster & more reliable. High level languages invented in this generation. 

Fourth Generation (1972-1980):

LSI & VLSI were used in this generation. As a result microprocessors came into existence. The computers using this technology known to be Micro Computers. High capacity hard disk were invented. There is great development in data communication. 

Fifth Generation (Present & Beyond):

Fifth generation computing devices, based on artificial intelligence, are still in development, though there are some applications, such as voice recognition, that are being used today. The use of parallel processing and superconductors is helping to make artificial intelligence a reality. Quantum computation and molecular and nanotechnology will radically change the face of computers in years to come. 

Architecture of Computer:

Input device: Those devices which help to enter data into computer system.

Output device: Those devices which help to display the processed information. 

Central Processing Unit: The main component to make a computer operate is the computer chip or microprocessor. This is referred to as the Central Processing Unit (CPU) and is housed in the computer case. Together, they are also called the CPU. It performs arithmetic and logic operations. The CPU (Central Processing Unit) is the device that interprets and executes instructions.