Electronic messaging may refer to:
One-to-one-communication Instant message (on a computer network) Personal message (on a computer network) Text message (on a cellular phone network) SMTP (on a computer network) Email (on a computer Network) Voicemail (using the PSTN) Fax (using the PSTN) Pager (using the PSTN)
One-to-many communication Bulletin board system (on a computer network) Internet forum (on a computer network) Usenet newsgroup (on a computer network)