Data Coding and Information Decoding

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Unique Code
Data consists of numbers, text, sounds, images, videos, etc. In order to define them in the real world, we are using numbers (0-9), letters (A-Z) and symbols (@,[,\, etc) or a combination thereof. For example:


 * 2012 (number)
 * Wikiversity (letters)
 * 3<5 (combination of numbers and symbols)
 * X=(Y*Z)+W-U (combination of alphabet and symbols)
 * N123 (combination of letters and numbers)

Computers, however, don't understand the definitions for numbers (0-9), letters (A-Z) and symbols (@,[,\, etc), so in order to process those pieces of information a unique code must be assigned to each of them. The unique code for numbers, letters, and symbols is a binary numeral. Data2 codeing.png



In practical use, each "0" and "1" in binary number uses a Physical attribute that is electrical or magnetic. The smallest part of that Physical attribute is named "Bit", the existence of the Physical attribute is "1", and the absence of the Physical attribute is "0"; 8 bits grouped up are called 1 Byte (so 1 byte=8 bits).

The binary numeral system, or base-2 number system, represents numeric values using two symbols - 0 and 1.

Examples:


 * numerical value " 0 " is 0. The unique code for 0 is →  00000000 
 * numerical value " 1 " is 1. The unique code for 1 is →  00000001 
 * numerical value " 2 " is 10. The unique code for 2 is →  00000010 
 * numerical value " 3 " is 11. The unique code for 3 is →  00000011 
 * numerical value " 4 " is 100. The unique code for 4 is →  00000100 
 * numerical value " 5 " is 101. The unique code for 5 is →  00000101 
 * numerical value " 6 " is 110. The unique code for 6 is →  00000110 
 * numerical value " 7 " is 111. The unique code for 7 is →  00000111
 * numerical value " 8 " is 1000. The unique code for 8 is →  00001000 
 * numerical value " 9 " is 1001. The unique code for 9 is →  00001001 

Alphabet (A,...Z):


 * The unique code for " A " is →  01000001 
 * The unique code for " B " is →  01000010 
 * The unique code for " C " is →  01000011 
 * The unique code for " D " is →  01000100 
 * The unique code for " E " is →  01000101 
 * The unique code for " F " is →  01000110 
 * The unique code for " G " is →  01000111 
 * The unique code for " H " is →  01001000 
 * The unique code for " I " is →  01001001 
 * The unique code for " J " is →  01001010 
 * The unique code for " K " is →  01001011 
 * The unique code for " L " is →  01001100 
 * The unique code for " M " is →  01001101 
 * The unique code for " N " is →  01001110 
 * The unique code for " O " is →  01001111 
 * The unique code for " P " is →  01010000 
 * The unique code for " Q " is →  01010001 
 * The unique code for " R " is →  01010010 
 * The unique code for " S " is →  01010011 
 * The unique code for " T " is →  01010100 
 * The unique code for " U " is →  01010101 
 * The unique code for " V " is →  01010110
 * The unique code for " W " is →  01010111 
 * The unique code for " X " is →  01011000 
 * The unique code for " Y " is →  01011001 
 * The unique code for " Z " is →  01011010 

for symbols :


 * The unique code for " @ " is →  01000000 
 * The unique code for " [ " is →  01011011 
 * The unique code for " \ " is →  01011100 



Distinction between "Data" and "Information"


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