How to open RAR files
4. Legal stuff
Unrar source may be used in any software to handle RAR archives
without limitations free of charge, but cannot be used to re-create
the RAR compression algorithm, which is proprietary. Distribution
of modified Unrar source in separate form or as a part of other
software is permitted, provided that it is clearly stated in
the documentation and source comments that the code may not be used
to develop a RAR (WinRAR) compatible archiver.