What is the difference between SMTP, POP, and IMAP?

Email is a technology built on several protocols that define message communication between servers and clients.

Sending and receiving emails across networks involves several distinct protocols. The most well known is probably SMTP, which is used by mailservers. IMAP, POP and POP3 are related technogolies used by many clients such as Mail.app and Outlook. Let's look more closely at each protocol.

What is IMAP?

IMAP (Internet Access Message Protocol), which is used to handle and retrieve messages from a receiving server, is one of the most helpful internet protocols. Yes, you cannot send emails with this; it is just used to manage and receive emails.

IMAP works with the SMTP protocol to transmit emails that are delivered and controlled by IMAP. Hence to continue successful email transmission, SMTP and a few additional protocols must also be used in addition to IMAP.

What Is SMTP?

SMTP stands for Simple Mail Transfer Protocol. The purpose of this protocol is to manage email-sending operations. If you want to send, forward, or relay an email, you must use SMTP. Whenever an email is transferred from the sender's computer to the IMAP server it is sent through an SMTP server.

What Is POP?

POP is short for (Post Office Protocol). Utilizing this protocol primarily serves to download emails from a server to a recipient machine. These emails are likewise deleted from the server following a successful download with the help of POP.

IMAP or SMTP assists in getting the email to the recipient server, but POP downloads it into the system once it has arrived. Therefore, these three protocols cooperate to move an email from the computer of the sender to the computer of the recipient.

What is POP3?

POP3 and POP have the same fundamental features. POP 3 is the third and most advanced version of post office protocol which is commonly used nowadays.

Difference Between IMAP And POP

POP3 downloads email from a host to a dedicated server before deleting it from the server.

IMAP on the contrary part integrates the message across several devices and saves it on a server.

Which one is more appropriate POP or IMAP?

IMAP is a robust choice and is preferred if you access your email from several devices. If you have an email-specific device and want to be able to view all of your emails while you're not connected to the internet, POP can be a decent option. In other words, the protocol you choose depends on how you access your emails and what are your fundamental email usage preferences.

Outgoing Email Transmission Through SMTP Relay Server

Whenever an email is transmitted from a server it is sent using an SMTP server. So SMTP relay service is used to start an email transmission process. Since SMTP relay is a cloud-based service you can easily attach it with an application instead of creating a separate mailing system.

To Sum Up

SMTP is the first protocol used for email transfer. This protocol uses an external SMTP relay service or an internal SMTP server to transmit emails. The email is received by IMAP once the SMTP server has completed its job. No doubt SMTP is one of the most commonly used protocols for receiving and synchronizing email data. Hence most applications use it for secure and steady email transmission.

IMAP is another important protocol used in email transmission. IMAP syncs the messages after receiving an email and controls the rest of the email transmission process.

In addition to IMAP and SMTP POP3 is also used for email transmission on a single device. When you are sending an email to only one device and you want to remove it from the server then you must use POP 3 as it will receive the email, download it and then delete it from the server.

Although there are additional internet protocols used in addition to these three, these are the most useful and important.