1. Applications: A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z 

oafd - the GNOME Object Activation Daemon.
objcopy - copy and translate object files
objdump - display information from object files.
od - dump files in octal and other formats
ogg123 - plays Ogg Vorbis files
oggdec - simple decoder, Ogg Vorbis file to PCM audio file (WAV or RAW).
oggenc - encode audio into the Ogg Vorbis format
ogginfo - gives information about Ogg files, and does extensive validity checking
ogonkify - international support for PostScript
oldps - report process status
onsgmls - An SGML System Conforming to International Standard ISO 8879 -- Standard Generalized Markup Language
openjade - apply a DSSSL stylesheet to an SGML or XML document
openvt - start a program on a new virtual terminal (VT).
osgmlnorm - An SGML System Conforming to International Standard ISO 8879 -- Standard Generalized Markup Language
ospam - An SGML System Conforming to International Standard ISO 8879 -- Standard Generalized Markup Language
ospent - Concatenate entities
osx - An SGML System Conforming to International Standard ISO 8879 -- Standard Generalized Markup Language