About the Computer :

“A Computer is an electronic machine that can solve different problems, process data, store & retrieve data and perform calculations faster and efficiently than humans”.

Meaning of the word "Computer" :

Computer is derived from a Latin word “computare” which means to “to calculate”,“to count”, “to sum up” or “to think together”. So, more precisely the word computer means a "device that performs computation".

Definition of Computer :

Computer is an electronic device that is designed to work with Information. The term computeris derived from the Latin term ‘computare’, this means to calculate or programmable machine. Computer can not do anything without a Program. It represents the decimal numbers through a string of binary digits. The Word 'Computer' usually refers to the Center Processor Unit plus Internal memory.

Charles Babbage is called the "Grand Father" of the computer. The First mechanical computer designed by Charles Babbage was called Analytical Engine. It uses read-only memory in the form of punch cards.

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.

Digital Computer Definition :

The basic components of a modern digital computer are: Input Device, Output Device, Central Processor Unit (CPU), mass storage device and memory. A Typical modern computer uses LSI Chips.  Four Functions about computer are:

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 Classification: By Size and Power:

Computers differ based on their data processing abilities. They are classified according to purpose, data handling and functionality.

According to functionality, computers are classified as: 

• Analog Computer: A computer that represents numbers by some continuously variable physical quantity, whose variations mimic the properties of some system being modeled.

• Personal computer: A personal computer is a computer small and low cost. The term"personal computer" is used to describe desktop computers (desktops).

• Workstation: A terminal or desktop computer in a network. In this context, workstation is just a generic term for a user's machine (client machine) in contrast to a "server" or "mainframe."

• Minicomputer: A minicomputer isn't very mini. At least, not in the way most of us think of mini. You know how big your personal computer is and its related family.

• Mainframe: It refers to the kind of large computer that runs an entire corporation.

• Supercomputer: It is the biggest, fastest, and most expensive computers on earth.

• Microcomputer: Your personal computer is a microcomputer.

 

Some interesting facts about computers & its Operating Systems :

⏹The first digital computers were developed between 1940 to 1945.

⏹Konrad Zuse, In 1941 developed “Z3”, the first modern computing machine.

⏹Konrad Zuse is regarded as “the inventor of computers”.
⏹ENIAC (Electronic Numerical Integrator & Computer) was the first US-built electronic computer.

⏹ENIAC was developed by John Mauchly and J. Presper Eckert.

⏹The world’s first stored-program computer was “Manchester Baby” developed in 1948.

⏹The “Manchester Baby” was a small-scale experimental computer developed in Victoria university of Manchester.

⏹In the 1^st generation of computers, Computers were built with vacuum tubes.

⏹In 1957, FORTRAN (Formula Translator) was introduced.

⏹Computers were built with Transistors in the 2^nd generation of computers.

⏹In the 3^rd generation of computers, Transistors were replaced with Integrated Circuits.

⏹In the 4^th generation of computers, Microprocessors were used to built Computers.

⏹In 1981, IBM PC with Intel processors and MS-Dos were introduced.

⏹In 1984, Macintosh Computers were introduced.

⏹In 1985, Microsoft Windows GUI was introduced.

⏹In 1989, Intel 486 computers were introduced.

⏹In 1990, Windows 3.0 operating System for PCs was launched.

⏹In 1991, the World Wide Web was introduced to the general public.

⏹In 1991, Linux operating was developed.

⏹In 1993, Intel’s Pentium was introduced.

⏹In 1995, windows 95 operating system was made released.

⏹In June, 1996 Windows 4.0 operating system was released.

⏹On February 17, 2000, Windows 2000 was released.

⏹Windows XP was released on 25^th October, 2001.

⏹On November 30^th, 2006 Windows Vista was released.

⏹On July 22^nd 2009, Windows 7 was introduced.

⏹On Windows 8, the successor of Windows 7 was released on October 28^th, 2012.