Neke mail skraćenice

MUA: Mail User Agent – The email application that a user sends/receives (thunderbird,pine,outlook)
MTA: Mail Transport Agent – The server agent responsible for sending the emails (sendmail,postfix,qmail)
MDA: Mail Delivery Agent – The server agent that accepts email from MTA, and places into users mailbox (procmail)
SMTP: Simple Mail Transport Protocol – MUAs and MTAs use this protocol for sending emails
POP3: Post Office Protocol (Ver 3) – MUAs use this protocol for receiving their emails from the final server
IMAP: Internet Message Access Protocol – MUAs can use this protocol to send and receive emails on the servers