.xz File — XZ Compressed File

XZ files use the LZMA2 compression algorithm, providing excellent compression ratios that typically exceed both gzip and bzip2 while offering faster decompression than bzip2. The XZ format was created by Lasse Collin and Igor Pavlov as the successor to the LZMA SDK format, standardizing a robust container with integrity checks (CRC-32, CRC-64, or SHA-256), multiple compression filters, and support for multi-threaded parallel compression. XZ has become the standard compression format for Linux software distribution — most Linux distributions use .tar.xz for package source archives, and kernel.org distributes Linux kernel sources in XZ format. The format achieves 20-30% better compression than gzip and 5-15% better than bzip2 for typical data, though compression speed is slower. Decompression requires relatively little memory and is fast enough for practical use. XZ Utils, the reference implementation, is included in virtually all Linux distributions. The format supports concatenation of multiple compressed streams, making it suitable for log files and append-only data. Parallel compression tools like pixz and pxz enable multi-threaded XZ compression.