CFD - computational fluid dynamics
CH - chemical engineering & chemistry
DB - database
DBG - debugger
DP - desktop publishing
DR - drawing
EE - electrical engineering
FEA - finite element analysis
GL - graphics library
GU - GNU utility
HE - HTML editor
IP - image processing & file format conversion
L - language
M - mailer & mail utility
MA - mathematics
MBIO - molecular biology
MP - man page reader & doc reader
NR - newsreader
PDF - PDF viewer
PL - plotting
PLS - plastics
PS - PostScript viewer
RA - rendering animation,
SH - shell
SE - search engine
ST - statistics
SU - shell utility
UT - utility
TE - text editor
VP - video player
WB - WWW browser
WS - window system
XU - X Window utility