Encoding and Decoding

Encoding

 is the process of putting a sequence of characters (letters, numbers, punctuation, and certain symbols) into a specialized digital format for efficient transmission or transfer. 

 Example :  Suppose we've to send APPLE. Encode by adding 'A' after every two characters

AP  A  PL  A E   =    APAPLAE

Decoding 

is the opposite process -- the conversion of a digital signal into a sequence of characters.

Decode converts the Encoded data to real format. 

Decode by removing  'A' after every two characters APAPLAE  = APPLE

Encoding  and  Decoding  process is used for secure data transfer.