GZIPcompressed

Gzip compressed refers to data that has been compressed using the gzip file format and utility. Gzip is a general‑purpose, lossless compression method commonly used to reduce the size of individual files or data streams. The term is often seen with the .gz extension and is widely supported on Unix-like systems and in many programming environments for both compression and decompression.

Gzip, short for GNU zip, was created as a free software replacement for the Unix compress utility by Jean-loup Gailly and Mark Adler. It was released in 1992 as part of the GNU project and has since become a de facto standard for file compression and web data transmission.

The gzip file format uses the DEFLATE compression algorithm, which combines LZ77 dictionary coding with Huffman coding. A gzip file contains a header, the compressed data blocks, and a trailer with a CRC-32 checksum and the size of the original data. The header stores metadata such as modification time and operating system information. Multiple gzip members can be concatenated to form a single file or stream.

Common applications include distributing software packages, log files, and web content. In HTTP, the Content-Encoding: gzip mechanism allows servers to send compressed responses, reducing bandwidth. For archives, gzip is often paired with tar to produce tar.gz or .tgz files.

Limitations and alternatives: gzip performs well on text and highly compressible data but less so on already compressed content. It is generally fast and widely compatible, but newer algorithms such as Brotli and Zstandard can achieve higher compression ratios or faster speeds for certain workloads.