What does the Post Office Protocol (POP) primarily do?

The Post Office Protocol (POP) is primarily designed to retrieve incoming email from a mail server. When a user sets up an email client to access their emails, it often uses POP as the protocol for downloading messages from the server. This process involves the client connecting to the mail server, authenticating, and fetching the email messages so that they can be stored locally on the user's device.

Once the emails are downloaded, they typically remain on the user's device unless specified otherwise, allowing them to access their emails without needing an ongoing connection to the server. This characteristic of POP makes it suitable for users who prefer to access their emails offline.

While the other options may describe functions related to email management, they do not accurately represent the primary purpose of POP. Managing outgoing emails refers to protocols like SMTP (Simple Mail Transfer Protocol), real-time chat services fall under different protocols designed for instant messaging, and while POP allows for offline storage, that is not its primary function; instead, its main capability is focused on retrieving emails from the server.