 More recently, Hàn Thế Thành and others have written a new implementation of TeX called pdfTeX, which also outputs to PDF and takes advantage of features available in that format.The XeTeX engine developed by Jonathan Kew, on the other hand, merges modern font technologies and Unicode with TeX.The default font for LaTeX is Knuth's Computer Modern, which gives default documents created with LaTeX the same distinctive look as those created with plain TeX.