Definition: netiquette

(NETwork etIQUETTE) Proper manners when conferencing between two or more users on an online service or the Internet. Emily Post may not have told you to curtail your cussing via modem, but netiquette has been established to remind you that profanity is not in good form over the network.

Using UPPER CASE TO MAKE A POINT all the time and interjecting emoticons throughout a message is also not good netiquette. See flame.