Data, Binary, Character sets, and Logical operations

Data, Binary, Character sets, and Logical operations

1. Data is made up of raw facts and figures - can be represented in different forms such as text and pictures

2. In order for data to be processed by a computer system, it must be in binary format

   • Computer systems can only store and process Binary digITs (BITs)
     • Either a 1 or 0
     • A binary number is a string of bits

3. A character set is a table that maps a character with a unique binary number

   • Unicode
     • Requires 16 bits - can represent a lot more characters
   • American Standard Code for Information Interchange (ASCII)
     • Only able to represent 128 different characters

4. A truth table for a logical operator defines the output for different combinations of input

5. Types of logical operator

   • NOT - only one input and output. The output is the opposite of the input
   • AND - two inputs and one output. The output is 1 only if A and B are both 1
   • OR - two inputs and one output. The output is 1 if either A or B is 1

6. Data types

   • Integer - whole numbers, positive or negative
   • Real - numbers, including fractions or decimal points
   • Character - letter, digit, space, or other symbol.s
   • String - a sequence of characters

7. Data storage units

   • Bit
     • 1 or 0
   • Nybble
     • 4 bits
   • Byte
     • 8 bits
   • Kilobyte
     • 1024 bytes
   • Megabyte
     • 1024 Kb
   • Gigabyte
     • 1024 Mb
   • Terabyte
     • 1024 Gb
   • Petabyte
     • 1024 Tb
   • Exabyte
     • 1024 Pb
   • Zettabyte
     • 1024 Eb
   • Yottabyte
     • 1024 Zb