PDFTeX (formerly known as TeX2PDF) arose from Han The Thanh's post-graduate research at Masaryk University, Brno, Czech Republic. The basic idea is very simple: to provide a version of TeX that can output PDF as an alternative format to DVI. PDFTeX implements a small number of new primitives, to switch to PDF output, and to control various PDF features. Han The Thanh has worked on PDFTeX throughout his Ph.D. research into typesetting, and the latest release includes facilities written to support novel typesetting techniques.
The latest version of PDFTeX is available on CTAN, and implementations are available as part the teTeX, mikTeX, fpTeX, and CMacTeX distributions (see TeX systems); it is also distributed on the TeX Live CDROM (see TeX CDROMs). A version (by the author of CMacTeX) for use with OzTeX is also available on CTAN.
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