A computer is an electronic device that processes data. It functions by simultaneously using two main components: Hardware and Software.

The Two Pillars of a Computer

1.Hardware

• The physical parts of the computer that you can see and touch.
• Examples: Keyboard, Mouse, Monitor, and internal components like the motherboard. 

2.Software 

• The programs and sets of instructions that run the hardware and tell the computer what to do.
• Examples: Web browsers (Chrome), Operating Systems (Windows), and office tools (PowerPoint, Word).

HISTORY OF COMPUTER

• ABACUS: It was the first calculating device of the computer, which was used to count numbers.
• Blaise Pascal (1642): Created the first mechanical computer, in which calculations were done without electricity.
• Charles Babbage (1833): Is known as the Father of Computers.
• The ENIAC (1942): (Electronic Numerical Integrator and Computer) was the world's first high-speed, electronic computer, developed by John P. Eckert and John W. Mauchly.

GENERATIONS OF COMPUTER

1st GENERATION (1946 - 1959):- 

• In this generation, vacuum tubes (this is a type of large electronic bulb, which used to work with the help of electricity) were used.
• They were very large in size, very heat-generating, and expensive.
• Example: ENIAC, EDVAC.
• Full Forms:
• ENIAC - Electronic Numerical Integrator and Computer.
• EDVAC - Electronic Discrete Variable Automatic Computer.

2nd GENERATION (1959 - 1965):- 

• In this generation, the transistor (it was like a small electronic device, which was used instead of a vacuum tube) was used.
• They were smaller in size, less hot, and more reliable.
• Example: IBM 1620, CDC 1604

3rd GENERATION (1965 – 1971):- 

• In this generation, IC (integrated circuits) was used. (It was a small chip that contains many transistors.)
• These types of computers are small and fast.
• Example: IBM-360 Series, PDP (Personal Data Processor)

4th GENERATION (1971 - 1980):- 

• VLSI (Very Large Scale Integration) was used in this generation. (It was a small chip that contains a lot of transistors.)
• These computers were cheaper, smaller and more reliable.
• Example: DEC 10, CRAY-1 supercomputer.

5th GENERATION (1980 - PRESENT):-

• In this generation, ULSI (Ultra Large Scale Integration) and AI (Artificial Intelligence) were used. (Artificial Intelligence gives computers the ability to think and understand.)
• These computers were cheaper, smaller, and more reliable.
• This type of computer is smart and fast, and it uses AI (Artificial Intelligence).
• They use advanced programming languages like C, C++, Java, and .Net.
• Example: PARAM 1000, IBM Watson.

TYPES OF COMPUTERS

ANALOG COMPUTERS

• These computers process data that is constantly changing.
• Ex- The speed, temperature, or pressure of a vehicle that changes with time.
• Ex- Speedometer (which shows the speed of the vehicle), Thermometer (which measures fever temperature).

DIGITAL COMPUTERS

• It processes data that is in 0 and 1 (binary language).
• They take raw data as input, process it, and show it to the result.
• Digital computers are the most used in today's time.
• Ex- Laptops, desktops, smartphones.

HYBRID COMPUTERS

• Such computers have both analog and digital features.
• They can process both constantly changing data (analog) and fixed data (digital).
• Ex- Computers installed at petrol pumps that measure both the quantity of petrol and its price. They show the quantity by converting it into analog and the price into digital data.

Quantum Computer

• These are computers based on a new technology that use quantum bits (Q-bits) instead of binary (0 and 1).
• Their processing speed is very fast and they will be faster than the supercomputers coming in the future.

FACTS

First Computer Program: Written by Ada Lovelace.

India's First Computer: Was "Siddhartha", which was established in Bengaluru.