A Mail Transfer Agent (MTA) is a software application responsible for transferring email messages from one computer to another using a client-server architecture. MTAs handle the sending, receiving, and relaying of email messages between mail servers. They use protocols such as Simple Mail Transfer Protocol (SMTP) to facilitate this process.
Key functions of an MTA include:
- Accepting outgoing email from a mail client or another MTA.
- Routing the email to the appropriate destination based on the recipient's email address.
- Delivering the email to the recipient's mail server.
- Handling retries and error reporting if the delivery fails.
Popular examples of MTAs include Postfix, Sendmail, and Exim.
