- k - bit message is represented by a binary vector of length k

Example, 01001100 --> (0,1,0,0,1,1,0,0)
 - k - bit code word  is represented by a binary vector of length n

Example, 01001100110 --> (0,1,0,0,1,1,0,0,1,1,0)
 - Transformation between message and code vectors.

 - In matrix form 

where

 - G Defines a Linear Systematic (n,k) Code

 - Example:

There are 8 unique code words

 - Problem: given a received message determine if an error has occurred.
 - Model for the received message

 - Define a Parity Check Matrix H
 

- Example:

An error has been detected.