Mail servers are computer systems or software applications that control e-mail communication. They act as servers to receive, forward, hold and send emails. This provides more independence and secure storage of data, i.e. they provide protection against unwanted access.
E-mails can be accessed from any Internet-enabled device using the appropriate access data. There are several modules in a mail server with different tasks. The mail transfer agent, for example, is responsible for receiving and forwarding emails. The mail delivery agent is responsible for sorting the emails in the mailboxes. Mail Retrieval Agents retrieve emails from other servers. The mail filter is responsible for blocking spam and malicious programs. The Global Address List (GAL) provides an address book from the mailboxes created on the mail server. The advantages of a mail server are, for example Protection and control of your own data through firewalls and filters, tariff changes or server failures are prevented and a lot of freedom in terms of storage space, addresses and restrictions on e-mail attachments.
Mail servers are important in the global e-mail system as they properly transmit e-mails from a sender to a recipient. They therefore ensure the availability and reliability of the email service.