There are important files in Mods and the regular WoP, which not many players know what they contain. 

Regular WoP files Edit

wop_001.pk3 - contains scripts, weapon effects, loadingscreens and such. 

wop_002.pk3 - contains the Weapon and Powerups models. 

wop_003.pk3 - contains the default maps and their levelshots

wop_004.pk3 - contains sounds and music files 

wop_005.pk3 - contains more scripts and textures 

wop_006.pk3 - contains extra stuff (extra scripts, textures etc.)

wop_padpack.pk3 - contains the maps, textures and objects from the PadPack. 

CTF files Edit

dtf_001.pk3 - contains all CTF map files, bot files and gametype files 

X-Mas Mod files Edit

Xmas3.pk3 - contains all new texture and model files, along with the Freezetag gametype files 

Other Edit

vm.pk3 - contains the external server commands, such as /Instagib and /NoPowerups