Notes on Lossless Data Compression and Huffman Coding

It is convenient to minimize the space needed to store data. Larger files will take longer to transfer over a data link, and will more quickly fill up disk quotas. Data compression techniques such as those used in common compression utilities allow reducing file sizes by exploiting redundancies in the data contained in them. Lossless coding techniques do this without compromising any information stored in the file. Lossy techniques may achieve even greater compression, but only by providing an approximate reconstruction of the original data. We discuss lossless binary coding, Shannon’s lower bound on the code length in terms of entropy, and the Huffman coding algorithm, a greedy approach to generating optimal prefix codes for lossless data compression.