What is the difference between POP3 and IMAP

POP3 and IMAP are protocols used to retrieve mail from a mail server's mailbox to the recipient's computer, both of which are Message Access Agents (MAA). So what's the difference between them? This article will introduce you to POP3 and IMAP and understand the difference between POP3 and IMAP. I hope it will be helpful to you.

What are POP3 and IMAP?

If you want to send and receive mail, you need two agents: a mail transfer agent and a mail access agent. The Mail Transfer Agent transfers messages from the client computer to the recipient's mail server; whereas, the Mail Access Agent's job is to retrieve the message from the mailbox on the recipient's mail server to the recipient's computer.

We have one mail transfer agent, SMTP (Simple Mail Transfer Agent); there are two mail access agents, POP (Post Office Protocol) and IMAP (Internet Mail Access Protocol). When senders and recipients of mail connect to a mail server over a WAN or LAN, two protocols are used: POP3 and IMAP.

POP3 Protocol:

is version 3 of the Post Office Protocol, which transfers email from a mailbox on the server to The user's local computer.

POP3 does not allow users to organize mail on the mailbox; users cannot create different folders on the server. Users cannot partially inspect the content of the email before downloading it. Users must download emails to read in POP.

IMAP Protocol:

IMAP (Internet Mail Access Protocol) is used to access mail from a mailbox on a mail server. Using IMAP, users can check email headers before downloading. Users are also able to inspect the content of an email for specific strings before downloading it.

If bandwidth is limited, using IMAP, users can partially download emails. Users can also create a hierarchy of these mailboxes within folders.

The main differences between POP3 and IMAP

1. Content access

Using the POP3 protocol, users must download emails before accessing them. However, using the IMAP protocol, users can partially inspect the email content before downloading.

2. Organize emails

Using the POP3 protocol, users cannot organize emails in the mailbox of the mail server. However, using the IMAP protocol, users can organize their mail on the server.

3. Mailbox operations

Using the POP3 protocol, users cannot create, delete or rename mailboxes on the mail server.

However, using the IMAP protocol, users can create, delete or rename mailboxes on the mail server; even users can create mailbox hierarchies in folders.

4. Download of emails

Using the POP3 protocol, users must completely download emails for reading. However, IMAP allows users to partially download emails when bandwidth is limited.

5. Functions

POP3 is simple with limited functions, while IMAP is powerful, complex, and has extra functions over POP3.

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