An email server is a computer system that manages the sending, receiving, and storing of email messages. It uses specific protocols, such as SMTP (Simple Mail Transfer Protocol) for sending emails and IMAP (Internet Message Access Protocol) or POP3 (Post Office Protocol) for retrieving them. Email servers can be hosted by organizations or provided by third-party services. They ensure that messages are delivered to the correct recipients and can store emails until the recipient is ready to access them. This infrastructure is essential for both personal and business communication in the digital age.