My theory about interacting on the Internet
Don't email anything to anyone that you wouldn't mind reading out loud 10 years down the road to everyone on Earth.
Don't write a journal entry, paper, or other item published on the Internet that you wouldn't mind reading out loud 10 years down the road to everyone on Earth.
Don't put up photos that you wouldn't mind showing in a very large slide show 10 years down the road to everyone on Earth.
Double check everything you publish on the Internet BEFORE you publish it.
Don't make jokes about your relatives--they could be computer illiterate but someone from work could tell them.
If you want to do these things, write them in a private journal. You know--one of those paper kind.