The Internet plays an important role as a means for worldwide social contact. The establishment and maintenance of social and group relationships within electronic worlds require social norms and behavioural conventions as in the real world. This paper investigates some of the available electronic media: Email, mailinglists, newsgroups, chatrooms, and MUDs. Peculiarities of the media are analysed through studying the documented behavioural norms and social conventions. We have looked at desired behaviour, disruptive behaviour and at sanction mechanisms. A conclusion that may be drawn is that within these virtual environments, explicitly documented norms and conventions play an underlying role in how individuals behave in addition to the type of behaviour that is expected from others.