Changes since version 3.20

New answers:
+Label spawnprog:   the \write18 mechanism for spawning programs
+Label whatengine:  am I running pdfTeX, XeTeX or luaTeX?
+Label write:       the \write primitive for writing text files

Relabelled answers:
<none>

Revised answers:
+Label biblatex:    mention bibtex8, even though biblatex+biber are winning
+Label codelist:    extend coverage of minted package (and Pygments)
+Label commercial:  remove Y&Y (not commercial any longer)
+Label dpfloat:     mention floatpage package
+Label drawing:     mention "embedded source" packages for asy, gplot, mp
+Label editors:     rationalise, removing "wildcard"
+Label filename:    add currfile, remove "DIY" code (which never worked right)
+Label floats:      update discussion of morefloats package, mention etex.sty
+Label fmtconv:     mention openoffice route for MS-word
+Label gethelp:     link "latex community" and "latex stack exchange"
+Label graphicspath: rephrase discussion of \graphicspath
+Label instt1font:  attempt to clarify updmap vs. updmap-sys
+Label labelfig:    mention (new) lpic package
+Label latex2html:  link to info on tug.org (note tex4ht now sourced there)
+Label mathml:      link to info on tug.org
+Label music:       rewritten following rearrangements on ctan
+Label nopagebrk:   discuss \pagebreak, \nopagebreak (!)
+Label papergeom:   discuss dvipdfm and its extensions
+Label psfchoice:   report one (at least) known problem with [pt]xfonts
+Label pspreview:   simplify, given that it's far less of a problem now
+Label ref-doc      remove link to NASA latex ref, add link to gna.org one
+Label textflow:    mention cutwin package
+Label tmupfl:      mention morefloats package, with caveats
+Label verbwithin:  mention cprotect package
+Label WYGexpts:    drop "activetex" -- seems no longer available
+Label zerochap:    rewrite for clarification

Deleted answers:
+Label ifpdf:       subsumed in new "whatengine" answer (link rerouted there)
+Label lollipop:    no longer relevant (a pity)

Web interface, etc.:
Some LaTeX command translations were broken, and have been mended
Work has started on a major reorganisation of the "fonts" section

Robin Fairbairns