Study Material for SSC CGL, CHSL, MTS, Prasar Bharti, FCI Exams : Coding-Decoding

Coding / Decoding

What is Coding-Decoding ?

For transmitting secret messages from one place to another, especially in defense services, Coding is used. Decoding is the ability to break the secret code. The codes are based on various principles or patterns.Questions based on coding-decoding could be given to judge the intelligence and mental ability of the candidates.

The coded word itself does not make any sense unless we know the coding principle. For coding-decoding, following basic knowledge is required.

1. Forward Order of Letters

A  B  C  D  E  F  G  H  I
1  2  3  4  5  6  7  8  9
J  K  L  M  N  0  P  Q  R
10 11 12 13 14 15 16 17 18
S  T  U  V  W  X  Y  Z
19 20 21 22 23 24 25 26

2. Reverse Order of Letters

A  B  C  D  E  F  G  H  I
26 25 24 23 22 21 20 19 18
J  K  L  M  N  0  P  Q  R
17 16 15 14 13 12 11 10 9
S  T  U  V  W  X  Y  Z 
8  7  6  5  4  3  2  1