Email clients vs mail servers: SMTP, IMAP, and POP3 roles

There are two components: email clients and mail servers.

Email clients

You use an email client (such as Gmail, Outlook, or Apple Mail) to compose an email. This client can be a web-based application or a standalone program.

Mail Servers

A mail server is a computer system that sends, receives, and stores email.

Types of Mail Servers

1. SMTP Server (Simple Mail Transfer Protocol).
   • Role: Handles the sending of emails.
   • Function: When you send an email, your email client communicates with the SMTP server, which then routes the email to the recipient’s mail server.
2. IMAP Server (Internet Message Access Protocol).
   • Role: Manages the receiving and storing of emails.
   • Function: Allows users to view and manage their email directly on the mail server. Emails remain on the server, and the client synchronizes with the server to display the latest emails.
3. POP3 Server (Post Office Protocol 3).
   • Role: Manages the receiving and downloading of emails.
   • Function: Downloads emails from the server to the client, usually removing them from the server after download. This means emails are stored on your local device.

SMTP

SMTP (Simple Mail Transfer Protocol). This protocol handles the sending of emails from your client to the mail server.

Checkers

• PHP: open_in_new PHP SMTP Checker .