Mail protocols

September 2, 2019

All mail is sent using an international protocol defined in 1982 and revisited in 2008 called SMTP (Simple Mail Transfer Protocol). While different mail services may use other protocols internally, they all use SMTP to communicate with each other.

On the receiving end of a mail, you also have a protocol to fetch new emails, in fact you have two wide used protocols: POP3 and IMAP.