Post Office Protocol (POP)

The Post Office Protocol (POP) is a standard way for email clients (like Outlook or Mail) to retrieve emails from an email server. When you check your email, POP downloads messages from the server to your local device, allowing you to read them offline. Once downloaded, the emails are typically removed from the server, meaning they are stored only on your device unless settings specify otherwise. POP is simple and effective for individual use, but it doesn't sync your emails across multiple devices—it's mainly designed for accessing your emails from a single device.