POP3
Post Office Protocol version 3
ELI5 — The Vibe Check
POP3 is the old-school way to receive email. It downloads all your emails to your device and (by default) deletes them from the server. It's like going to a post office to pick up letters — once you take them home, they're gone from the post office.
Real Talk
POP3 is a protocol for retrieving email from a mail server to a local client. Unlike IMAP, it downloads emails and typically removes them from the server. It offers limited synchronization between devices. Operates on port 110 (or 995 with SSL/TLS). Largely superseded by IMAP for modern use.
When You'll Hear This
"The old email client uses POP3 and deletes messages from the server." / "Switch to IMAP instead of POP3 if you access email from multiple devices."
Related Terms
IMAP (Internet Message Access Protocol)
IMAP is how your email client fetches email from the server.
Port
A port is like an apartment number on a building. Your computer is the building (localhost), and multiple services live inside.
SMTP (Simple Mail Transfer Protocol)
SMTP is the protocol email uses to leave your device and travel to the recipient's mail server.