In computer engineering, compression is the term used for the reduction of the memory space required for data by optimizing the binary notation of the information. Depending on the nature of the original data and their coding, compression ratios of 1 : 100 and more can be achieved in this way, thus saving memory space and/or transfer time. A distinction is made between compression methods that involve a (more or less acceptable) loss of information and non-lossy methods. Typical lossy methods are JPEG for images and MP3 for music. Methods for compressing numerical data, such as MNP5 and V.42bis for data transmission, and also compression methods for files (zip, lha, rar, etc.), are of the non-lossy type for obvious reasons.
- Data Compression