Definitions computers hardware basic Coding Schemes Computer Peripherals

In this article we would discuss about coding schemes used in computer, definition of computer. Later we would cover measurement unit used in computer storages.

What is a Computer?

• An electronic machine
• that can be programmed to
• accept data (input), and
• process it into
• useful information (output).
• Kept in secondary storage (storage) for safekeeping or later use.
• The processing of input into output is directed by the software, but performed by the hardware
•   Bits & Bytes
  Computers are devices powered by electricity, which has two discrete states: On or Off.
  Two digits represent these states:
   
  
  
  
• • To be processed, all data in a computer system (words, symbols, pictures, videos, sounds) must be reduced to a string of binary digits.
  • A binary digit 1 or 0 is called a bit,
  • Eight bits grouped together as a unit are called a byte, which provides enough combinations of 0s and 1s to represent 256 individual characters, including numbers, upper and lower case alphabet letters, punctuation marks and other characters

  Name	Abb	Approx. Bytes	Exact Bytes	Approx. Pages of Text
  Byte	B	One	1	One character
  Kilobyte	KB (or K)	One thousand	1,024	One-half page
  Megabyte	MB	One million	1,048,576	500 pages
  Gigabyte	GB	One billion	1,073,741,824	500,000 pages
  Terabyte	TB	One trillion	1,099,511,627,776	500,000,000 pages

  Coding Schemes
  Define the patterns of bytes
  Coding schemes, such as ASCII, EBCDIC, and Unicode, provide the means to interact with a computer
  When a letter is pressed on a keyboard, the electronic signals are converted into binary form and stored into memory.
  The computer processes the data as bytes of information and converts them to the letters we see on the monitor screen or on a printed page.
  
• Terminology
  • Hardware (H/w) All machinery & Equipments Computer & Peripherals
  • Peripherals Any piece of hardware connected to the PC
  • Software (S/w) programs- tells the Computer how to perform a task
  • Systems Software (S/w) For managing internal activities & run applications s/w Interpreter bet S/w & H/w
  • Application Software (S/w) - to perform a specific task Custom or Packaged