1. Knuth's & Levy's C/C++ programming system. CWEB allows you to write documents which can be used simultaneously as C/C++ programs and as TeX documentation for them. The philosophy behind CWEB is that programmers who want to provide the best possible documentation for their programs need two things simultaneously: a language like TeX for formatting, and a language like C for programming. Neither type of language can provide the best documentation by itself. But when both are appropriately combined, we obtain a system that is much more useful than either language separately. You may also want to install the ctie package which allows one to work with multiple change files simultaneously. From Debian 3.0r0 APT