It is a compressed archive format known for its high compression ratio (often 30–70% better than ZIP) using the LZMA/LZMA2 algorithm. It is frequently used for large data sets, firmware, or software distributions.
: The format supports AES-256 encryption , so if the file headers are encrypted, you will be prompted for a password before you can even see the file names. Online Viewers
: You can also use WinZip to open and extract 7z files if that is your preferred archiver.