As discussed in the Introduction,data compression has wide application in terms of information storage,including representation of the abstract data type string and file compression.Huffman coding is used for compression in several file archival systems [ARC 1986; one of the adaptive schemes to be discussed in Section 5.An adaptive Huffman coding technique is the basis for the compact command of the UNIX operating system.
one could expect to see even greater use of variable-length coding in the future.