Some people list themselves on the wiki
Player List. Others you learn because you've trolled this forum long enough to know who's-who. Others you're pretty sure you know because you've trolled here long enough, but you're not 100% sure. Then there are the new faces you won't know for a while because they're new, and finally there are the forum names of people that just troll the forum and that don't even play P99 (or at least not anymore).