Verbal - Coding and Decoding
The term Coding-Decoding primarily relates with message sent in secret form which can not be understood by others easily. Coding, therefore, means rule or method used to hide the actual meaning of a word or group of words and Decoding means the methods of making out the actual message that is disguised in coding.
A Code is a system of Signals. Therefore, Coding is a method of transmitting a message between the sender and receiver.
Questions of Coding-Decoding are designed to test candidate's ability to understand the rule used for coding and then translate it quickly to find out the coding for the given word.