[me2i81]

Bah. Knuth wrote several interesting applications, including one that changed the face of mathematics more in the last 20 years than any other development. Where would math be without TeX? But beyond that, there's more to CS than "novel applications," and Knuth has been one of the most important theoretical computer scientists in the world, and was one of the fathers of the field, inventing asymptotic analysis of algorithms, inventing the parsing algorithms used by nearly every compiler on the planet, and on and on.

[amichail]

Is TeX really a novel app in the sense that twitter say is?

In fact, TeX isn't even the first of its kind.

[gchpaco]

TeX was the first serious examination of what good typographical layout was and how to codify it. Previously there were many rules of thumb, and lots of examples, and a handful of programs for typesetting (like RUNOFF, which was and is pretty damned ugly, although it beats the pants off a typewriter) but in TeX Knuth created an algorithm for things like mathematical layout, for paragraph layout. I am unaware of anything that has surpassed TeX in this field—programs like Lout use the same algorithm TeX does, just with a less idiosyncratic surface syntax and with a rewritten core.

[amichail]

TeXmacs has a typesetter with real-time WYSIWYG editing that is comparable in output to TeX. So TeX has been surpassed in that sense.

[ramchip]

I think comparing TeX to twitter is a serious insult to TeX.

[eru]

Which computer type setting system do you know that preceded TeX and produces beautifully typeset text and mathematics?

[amichail]

http://en.wikipedia.org/wiki/Troff

[wglb]

troff did not produce beautiful typeset mathematics, nor did it even pretend to deal with fonts.

[gchpaco]

Strictly speaking it is possible to use fonts other than R, B, I, BI using ".fn" but because the set of fonts is determined by the output device it's very limited.

Much to my surprise GNU groff's font format does actually contain kerning information and ligatures although it's quite primitive and none of the included fonts have characters much outside of Latin-1 (to the point that there's a specialized "EURO" font you have to use if you want a Euro symbol). I would have to go over the older documents I have to be sure but I don't think this was a feature of the original troff.

[eru]

But - is it as beautiful?

[amichail]

Twitter is a greater conceptual leap over blogging than TeX is over troff.

[wglb]

Not really. Twitter is microblogging. TeX greatly expanded the quality and re-usability of very difficult typeset documents.

[eru]

Perhaps. Still, TeX feels like an accomplishment. (Though as a programming language it's close to horrible.)