PSTricks offers an extensive collection of macros for generating PostScript that is usable with most TeX macro formats, including Plain TeX, LaTeX, AMS-TeX, and AMS-LaTeX. Included are macros for colour, graphics, pie charts, rotation, trees and overlays. It has many special features, including a wide variety of graphics (picture drawing) macros, with a flexible interface and with colour support. There are macros for colouring or shading the cells of tables. The package pstricks-add contains bug-fixes and additions for PSTricks (among other things). PSTricks ordinarily uses PostScript \special commands, which are not supported by pdf(La)TeX. This limitation may be overcome by using either the pst-pdf or the pdftricks package, to generate a PDF inclusion from a PSTricks diagram. PSTricks macros can also generate PDF output when the document is processed XeTeX, without the need for other supporting packages.