Email protocols

Email protocols

1. SMTP

   • SMTP message formats require a message header and a message body. While the message body can contain any amount of text, the message header must have a properly formatted recipient email address and a sender address.

2. POP

   • Used by an application to retrieve mail from a mail server. With POP, mail is downloaded from the server to the client and then deleted on the server.

3. IMAP

   • When the user connects to an IMAP-capable server, copies of the messages are downloaded to the client application. The original messages are kept on the server until manually deleted.