The term chatiquette (chat etiquette) is a variation of netiquette (internet etiquette) and describes basic rules of online communication. To avoid misunderstandings and to simplify the communication between users in a chat these conventions or guidelines have been created. Chatiquette varies from community to community, generally describing basic courtesy; it introduces new user into the community and the associated network culture. As an example, it is considered rude to write only in upper case, because it looks as if the user is shouting. The word chatiquette has been used in connection with various chat systems (e.g. IRC) since 1995.
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