On 2018-03-04 4:00 PM, Bakul Shah wrote: > > > On Mar 4, 2018, at 12:42 PM, Clem Cole > wrote: > >> >> On Sun, Mar 4, 2018 at 3:23 PM, Doug McIlroy > > wrote: >> >> >> I hadn't realized that groff hyphenation had been taken from >> Tex, not troff. Is that becuase Tex did a better job, or >> because troff's was deemed proprietary? >> >> Given the author, I would guess the later as he wanted to be FOSS and >> would not have looked at the ditroff source - but that guess is worth >> just that ;-) > > I remembered reading about Knuth's line-breaking  algorithm in > Software Practice & Experience in early eighties and being quite > impressed with it. So may be that clear description of the algorithm > has something to do with it? Ah, here it is: > > “Breaking Paragraphs into lines” by Donald Knuth & Plass, > SP&E, Volume 11, issue 11, Nov. 1981 That's the line breaker, which is an important contributor to the quality of TeX output. But TeX's *hyphenation* algorithm per se was invented by Franklin Mark Liang and was indeed considerably better than its predecessors and competitors (including most or all commercial typesetting software -- which was a big part of the motivation for it): https://tug.org/docs/liang/liang-thesis.pdf --Toby > > (Download from Wiley is not free) > > >