Huffman encoding is a lossless data compression algorithm where the input characters are represented by variable length codes (Prefix codes). These codes are based on the frequency in which the character appears. More common inputs are represented by smaller codes and the lesser common inputs are represented by bigger code. To do this efficiently, it can use a min heap tree ( where the lowest frequency will have the highest priority).

Huffman encoding is not always optimal and can be replaced by other entropy encoding forms such as arithmetic coding.