The language shares Metafont's declarative syntax for manipulating lines, curves, points and geometric transformations.
The encapsulated postscript produced by Metapost can be included in LaTeX, ConTeXt, and TeX documents via standard graphics inclusion commands.
The encapsulated postscript output can also be used with the PDFTeX engine, thus directly giving PDF.
This ability is implemented in ConTeXt and in the LaTeX graphics package, and can be used from plain TeX via the supp-pdf.tex macro file.
To view or print the third diagram, this inclusion is necessary, as the TeX fonts (Computer Modern) are not included in the eps files produced by MetaPost by default.