TeX
Another major publishing standard is TeX, created and continuously refined by Donald Knuth in the 1970s and ’80s. TeX concentrated on detailed layout of text and font descriptions in order to typeset mathematical books in professional quality. This required Knuth to spend considerable time investigating the art of typesetting. However, TeX has a steep learning curve, so that it is mainly used in academia, where it is the de facto standard in many scientific disciplines. A TeX macro package known as LaTeX provides a descriptive markup system on top of TeX, and is widely used.