Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. Majority logic decoding is a method to decode Repetition codes, based on the assumption that the largest number of occurrences of a symbol was the transmitted symbol.If we have a binary alphabet made of 0,1 and we use an (n,1) repetition code, then we have each input bit mapped to the codeword as a string of n-replicated input bits. We generally choose n = 2t + 1, an odd number. Repetition code is an (r,1) coding scheme that repeats the bits across a channel to achieve error free communication (r is the number of bits in each codeword for each data bit to be coded). Repetition code is generally a very naive method of encoding data across a channel, and it is not preferred for Additive White Gaussian Noise Channels (AWGN), due to its worse-than-the-present error performance. Repetition codes generally offer a poor compromise between data rate and bit error rate, and other forms of error correcting codes can provide superior performance in these areas. The chief attraction of the repetition code is the ease of implementation.