Reg
"Reg" is slang terminology for a regular poster in a BBS, newsgroup, blog, or any kind of online community. They have generally been community members for a long period of time. Because of this they often are the first candidates for moderators.
Regs constitute a small minority of the community members but contribute most of the content in the community. They are conscious of their situation in the community and often react strongly against newcomers because they consider them to be outsiders. Others in the other hand are very welcoming towards them and even form a sort of "welcome troupe".
See also
Categories: Website stubs | Customary categories of people | Internet slang