Postfix is a free and open-source mail transfer agent (MTA) used for routing and delivering electronic mail. It is an alternative to the widely used Sendmail program. Designed with a focus on security, speed, and ease of administration, Postfix is known for its efficiency and low maintenance requirements. It works by receiving emails from a mail client (MUA), processing, and then forwarding them to the appropriate recipient's mail server (MSA/MTA). Postfix is highly customizable and widely used in various mail server configurations in web hosting environments.
