PGF is a macro package for creating graphics. It is platform-
and format-independent and works together with the most
important TeX backend drivers, including pdfTeX and dvips. It
comes with a user-friendly syntax layer called TikZ. Its usage
is similar to pstricks and the standard picture environment.
PGF works with plain (pdf-)TeX, (pdf-)LaTeX, and ConTeXt.
Unlike pstricks, it can produce either PostScript or PDF
output.