combine is free software, which allows a user to make connections between files, and thus make the file joins. combine is free software, which allows a user to make connections between files, and therefore make the attachment, clusters, and frequencies. combine is part of the GNU Project. When built on a system with available Guile, Guile uses it to provide extensibility for filtering and processing data. Additional features include handling hierarchy, a Guile module adapted from the calendar Emacs for operations date, and outer joins on one or both sides of a game. Version 0.3.3 is the first GNU version, and has some compatibility improvements. Guile is a very strong dependence, for all the extensibility features. The program does seem to be based fine without Guile, although some features are not available. combination is known to have successfully compiled on GNU / Linux, Mac OS X and HP-UX. A first version failed on an AIX system, but I lost contact with this user. Please let me know if you have success or problems in its construction.