Email servers and clients communicate with one another using protocols. While there are dozens, if not hundreds, of telecommunications protocols, thankfully email only involves a few.

Here are some of the more common ones found in the modern implementation and use of email:

It took me awhile to get a clear understanding of what each on is specifically used for, so I'll share my thoughts with you:

  • SMTP is used for sending, receiving, and relaying email
  • IMAP is typically used for accessing email on a server store from multiple clients
  • POP is typically used for downloading email from a server to a single client