RAR is a proprietary data compression and achieve algorithm, developed by Russian programmer Eugene Roshal (hence the name RAR: Roshal Archive). RAR compression algorithm is typically slower than other compression algorithm such as ZIP, but can usully achieve much better compression ratio. RAR also supports splitting archives into smaller, equal sized pieces and password protection of compressed achieves using the AES encryption algorithm. Variable amounts of redundancy (“recovery record”) can be embedded into an archive, making it more resistant to corruption; thus even if parts of an archive are damaged, it may still be possible to fully recover the stored data if enough recovery record exists.
WinRAR is the RAR GUI developed by Eugene Roshal for Windows operating systems. Its interface can be customized using theme files.