TikZ and PGF are TeX packages for creating graphics programmatically. TikZ is build on top of PGF and allows you to create sophisticated graphics in a rather intuitive and easy manner.
Disclaimer: This site is not the official home of TikZ and PGF. Consult the Sourceforge project page for releases, support and bug reports.
Track the development of TikZ and PGF.
A package for creating timing diagrams.
A package for drawing Bode, Nichols-Black and Nyquist diagrams.
Provides facilities for linking elements of an amsmath align or aligned environment.
A package that provides macros for creating tables showing signs and variations of functions.