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|
|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|
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.
- 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