gzipped

Gzipped refers to data that has been compressed using the gzip compression tool and file format. Gzip uses the DEFLATE compression algorithm, which combines LZ77 and Huffman coding to reduce file size. The resulting gzip file typically has a .gz extension and is designed for fast compression and decompression with minimal CPU usage. The format includes a small header with metadata and a CRC-32 checksum in the footer to verify integrity.

Gzipped data are commonly used for single-file compression. When multiple files need to be combined, they are often first archived with tar and then compressed with gzip, creating a .tar.gz or .tgz file. This two-step approach is widespread in Unix-like environments and other systems that support gzip and tar utilities. The gzip file format is defined in RFC 1952, while the DEFLATE algorithm is specified in RFC 1951.

Usage and tooling are broad and cross-platform. On most systems, gzip and gunzip commands are available, and gzip can be used in pipelines to compress data stream on the fly. Common commands include gzip to compress, gunzip to decompress, and zcat to view compressed content without full extraction. Web servers frequently serve gzipped content to reduce bandwidth needs, while software distributions often ship gzip-compressed archives to minimize download sizes. Gzipped data are most effective on plain text and other highly compressible content but offer diminishing returns for already compressed media formats.

Limitations include reduced effectiveness on already compressed data and potential compatibility considerations when transferring compressed files between very different environments. Overall, gzip remains a widely adopted standard for practical, fast compression in many computing contexts.