Data Representation

Data Representation

1. units of data

   • Bit, Nibble, Byte, Kilobyte, Megabyte, Gigabyte, Terabyte

2. Binary Numbers

   • Binary allows ont two numbers 0 and 1

3. Binary addition

   • when adding two numbers there are only 5 possible outcomes
     • 0 + 0 = 0
     • 0 + 1 = 1
     • 1 + 0 = 1
     • 1 + 1 = 10
     • 1 + 1 + 1 = 11

4. overflow

   • A CPU with a capacity of 8 bits has a capacity of up to 11111111 in binary. If one more bit was added there would be an overflow error.

5. Hexadecimal numbers

   • Hexadecimal is another numbering system, also known as base 16.
     • There are 16 available digits - 0,1,2,3,4,5,6,7,8,9,A,B,C,D,E and F.

6. Characters

   • ASCII
     • ASCII character require only seven bits, needs less storage space but can only store 128 characters
   • Unicode
     • Unicode require 16 bits, needs more storage space but can store 65,536 different characters

7. Images

   • An image is divided into pixels, each of which is a tiny dot on the screen

8. Sound

   • Sampling rate
     • its how often the computer takes a measure of the sound
       • higher sampling rate, better sound quality
   • Bit rate
     • its how many bits are used for each samples
       • higher bit rate, higher quality of sound

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