What's In There?

Standard C library.

Compilers - C, C++, Fortran, Assembly, Pascal, Java...

Scripting languages - sh, ksh, csh, perl, python, tcl, php.

Multi-process and multi-threading (pthreads) APIs, IPC mechanisms...

Text-mode support - termcap, terminfo, curses/ncurses...

X11R6 - Xlib, X toolkit, Athena widgets, Motif/Lesstiff...