A file with .tbz extension is a compressed archive that uses BZIP compression for reducing the size of the content files. The TBZ files are actually UNIX TAR archived files that are compressed with BZIP then. The most recent second level compression is BZIP2 that replaced BZIP. TBZ file format is suitable for transferring large files. TBZ files can be opened/extracted using software applications such as 7-Zip, PeaZip, and jZip. Linux and macOS users can also open a TBZ with the BZIP2 command from a terminal window.
TBZ File Format
TBZ files are actually compressed archives created with BZIP/BZIP2 compression. There are no formal specifications available for this file format. However, an unofficial reverse engineered specifications show that a .bz2 stream consists of a 4-byte header which is followed by zero or more compressed blocks.