A standard email protocol used for retrieving and downloading emails from a mail server to a local email client. POP allows users to access their email messages stored on a server, download them to their device, and manage them locally. The most common version, POP3, facilitates this by connecting to the mail server, downloading the emails to the client, and typically removing them from the server. This means that emails are stored on the user’s device rather than on the server, which can be useful for offline access but limits the ability to access emails from multiple devices. POP is designed for straightforward email retrieval and management.