What component of email communication routes messages from the sender to their destination?

The mail transfer agent plays a crucial role in the routing of email messages from the sender to their intended destination. It is responsible for receiving outgoing email messages from the mail user agent (the software used by the sender to compose and send emails), and then it processes these messages to find out where to deliver them. This involves determining the recipient's mail server through DNS (Domain Name System) queries and managing the delivery process, which may include storing the message temporarily if the recipient's server is unavailable.

Once a message is sent, the mail transfer agent uses protocols like SMTP (Simple Mail Transfer Protocol) to transfer the message across the internet. This process may involve several mail transfer agents if the sender and recipient are using different email providers. Ultimately, the mail transfer agent ensures that emails are routed efficiently and accurately to their final destination, making it a fundamental component of email communication.