TeXShop is a TeX previewer for Mac OS X, written in Cocoa. Since pdf is a native file format on OS X, TeXShop uses "pdftex" and "pdflatex" rather than "tex" and "latex" to typeset; these programs in the standard teTeX distribution of TeX produce pdf output instead of dvi output.

TeXShop uses TeXLive and teTeX, standard distributions of Tex programs for Unix machines. The distributions include tex, latex, dvips, tex fonts, cyrillic fonts, and virtually all other programs and supporting files commonly used in the TeX world.