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.