2.3 Summary
In this part you have seen examples of the two broad categories of error control codes: an error detecting code (the EAN-13 code) and an error correcting code (RS code).
All error control involved the addition of redundancy to a message. If the number of message bits (or bytes) is k, and the augmented length after the addition of redundancy is n bits (or bytes), the ratio k/n is the code rate.