MetaPost is a programming language much like Knuth’s METAFONT except that it outputs either vector graphics in the PostScript or SVG formats or bitmap graphics in the PNG format. Borrowed from METAFONT are the basic tools for creating and manipulating pictures. These include numbers, coordinate pairs, cubic splines, affine transformations, text strings, and boolean quantities. Additional features facilitate integrating text and graphics and accessing special features of PostScript such as clipping, shading, and dashed lines. Another feature borrowed from METAFONT is the ability to solve linear equations that are given implicitly, thus allowing many programs to be written in a largely declarative style. By building complex operations from simpler ones, MetaPost achieves both power and flexibility.
MetaPost is particularly well-suited to generating figures for technical documents where some aspects of a picture may be controlled by mathematical or geometrical constraints that are best expressed symbolically. In other words, MetaPost is not meant to take the place of a freehand drawing tool or even an interactive graphics editor. It is really a programming language for generating graphics, especially figures for TEX3 and troff documents.