Winn L. Rosch Hardware Bible, Sixth Edition

Data Compression

Just as virtual memory can stretch the capacity of your primary storage system, data compression can boost the capacity of your secondary storage system. Compression eliminates the waste in a storage system. It seeks to put every bit of information in the smallest possible space. In effect, the compression system squeezes the air out of the data stream. Data compression can reduce fat files into their slimmest possible representation, which can later, through a decompression process, be reconstituted into their original form.

Most compression systems work by reducing recurrent patterns in the data stream into short tokens. For example, the two-byte pattern “at” could be coded as a single byte, such as “@”, thus cutting the storage ...