E-Mail, newsgroups, and forums

Formats for the storage or transmission of messages (singly or in groups) for electronic mail, discussion lists, forums, newsgroups, BBSs, social networking, etc. See also Web, Address books and contacts.

Abbreviations, conventions, etc. in messaging
Online messages can be a language all their own, with different dialects for different types of messages, but often "leaking" from one service to another. Here are a few of the things to watch out for:
 * Emoticons - smileys, frowneys, etc :-)
 * Hashtags, at-signs, retweets, etc. - Twitterisms that often turn up elsewhere
 * Txtspeak - various abbreviations sometimes used in chats

Bulletin Board Systems (BBSs)
If Google was an '80s BBS...

Programs

 * Fido BBS
 * Opus-CBCS (BBS software)
 * Opus Embedded Commands (OEC)
 * PCBoard

Networks, protocols and formats

 * AVATAR
 * EMSI/IEMSI
 * FidoNet message packet
 * FidoNet nodelist
 * FidoNet nodediff
 * FIZ (archiver used with Maximus BBS software)
 * FOSSIL
 * Wazoo
 * XMODEM
 * YMODEM
 * YooHoo
 * ZMODEM

Chat, Texting and Instant Messaging

 * AOL Instant Messenger
 * ICQ
 * IRC (Internet Relay Chat)
 * Puffchat
 * SMS (text messaging on phones)
 * Slack
 * Snapchat
 * XMPP (Jabber)

Standards and protocols

 * Bang path
 * Habeas Warrant Mark
 * IMAP
 * Internet e-mail message format (RFC 733/RFC 822/RFC 2822/RFC 5322)
 * List-Unsubscribe header
 * Maildir
 * MAPI
 * mbox
 * POP3
 * QWK
 * SMTP
 * SOUP
 * SPF
 * T.37 (fax to e-mail)
 * UUCP
 * X-Face

Clients

 * AOL
 * AOL e-mail messages
 * AOL Personal Filing Cabinet (includes e-mail as well as other things)
 * Apple Mail
 * Blue Wave
 * Eudora
 * Lotus Notes
 * Notes Storage Facility (NSF)
 * Mailpile
 * Microsoft Entourage
 * Microsoft Outlook
 * Nickfile (NK2)
 * Personal Folder File (PAB, PST, OST)
 * Outlook for Mac Data File (OLM)
 * Outlook Item File (MSG)
 * Microsoft Mail (.mmf) Discontinued in 2002
 * MLM (Novell Groupwise)
 * Outlook Express Database (DBX)
 * Pegasus Mail
 * Pine
 * Thunderbird
 * Thunderbird Message File

Servers

 * Mercury
 * Microsoft Exchange

Webmail services

 * Gmail
 * Hotmail
 * ProtonMail

E-mail archiving

 * Mailbag
 * Sonasoft

Forums / web comment threads

 * Discourse
 * Disqus
 * Google Groups
 * phpBB
 * Yahoo Groups

Messaging service integration

 * Slack

Online Services
(the old, proprietary variety)


 * AOL
 * CompuServe
 * Prodigy
 * The Source

Secure messaging
See also Encryption, Security


 * ByLock
 * Confide
 * Crypho
 * PGP
 * PKCS7
 * Privacy-Enhanced Mail (RFC 1421)
 * ProtonMail
 * SafeSlinger
 * saltpack
 * SecureDrop (was DeadDrop)
 * Silent Circle Instant Messaging Protocol
 * S/MIME

Social Networking

 * Discord
 * Ello
 * Facebook
 * Friendster
 * Google+
 * Instagram
 * LinkedIn
 * Mastodon
 * MySpace
 * nostr
 * Pinterest
 * pump.io
 * Quora
 * Reddit
 * Snake
 * SSB (Secure Scuttlebutt)
 * Tumblr
 * Twister
 * Twitter

Transfer Encodings
This is an incomplete list. For more, see the main Transfer Encodings article.


 * Base64
 * MIME
 * MIME types
 * Quoted-printable
 * Transport Neutral Encapsulation Format (TNEF; winmail.dat)
 * Uuencoding
 * Xxencoding
 * yEnc

Usenet

 * Bang path
 * NZB
 * Usenet message format (RFC 850/RFC 1036/RFC 5536/RFC 5537; Discussion of early Usenet format)
 * UUCP

BBSing

 * Lots of vintage BBS software
 * Modems, wArEz, and ANSI art: Remembering BBS life at 2400bps
 * Elite Exchange One BBS software manual (1989)
 * BBS-related podcasts
 * ERIC ED325112: Electronic Bulletin Boards. (April 1986)

Email

 * Mail Chauvinism: The Magicians, the Snark and the Camel -- Ted Nelson, 1981
 * How to self-host your own mail server in the cloud
 * NSA Says It Can’t Search Its Own Emails (Just everybody else's!)
 * How can I find out where an email really came from?
 * New Encrypted Email Services Coming From Kim Dotcom's Mega And Newzbin
 * Dark Mail Alliance - developing end-to-end encryption for e-mail
 * TorBirdy: extension to use Tor encryption with Thunderbird
 * The Daunting Challenge of Secure E-Mail
 * Verify e-mail addresses online
 * Yahoo breaks every mailing list in the world including the IETF's
 * The End of History: How e-mail is wrecking our national archive (ironically, the article succumbed to linkrot, but is retrievable from the Internet Archive)
 * E-mail self-defense guide (encryption)
 * Carcanet Press Email Preservation Project - Phases 2-3
 * Framework and Functions of the "MS" Personal Message System (David H. Crocker, 1977)
 * E-mail client market share
 * EPADD: software for cataloguing e-mail archives
 * The 100% Correct Way to Validate E-Mail Addresses
 * The Future of Email Archives: A Report from the Task Force on Technical Approaches for Email Archives

Newsgroups/Usenet

 * Kickstarting Operator: a censorship-resistant, shape-shifting newsreader
 * olduse.net: "Real time" posting of 30-year-old Usenet posts

Social networking

 * LinkedIn ‘Intro’duces Insecurity
 * Free download of danah boyd's must-read book "It's Complicated" (about young people and social networking)
 * A Dynamic New Tool to Preserve the Friendsters of the Future (NY Times Blogs)
 * A Teenager’s View on Social Media
 * A 1980 Teenager’s View on Social Media
 * An Old Fogey’s Analysis of a Teenager’s View on Social Media

Misc.

 * Online, Underground: In-progress written history of online messageboards
 * Opt out of PRISM: surveillance-free alternatives to things including social networking and messaging
 * India to send world's last telegram. Stop.
 * PLATO: The Emergence of Online Community
 * The Minitel: France's 1980s "Internet"
 * LOLCats and Libraries: A Conversation with Internet Librarian Amanda Brennan (on the study of Internet memes)