Both IMAP and POP came way before the world got hooked on emails. These are protocols to get access to emails from the servers and are responsible for highly successful clients like Outlook and Apple Mail.
IMAP and POP
But do you know what they are exactly?
This post below discusses about them in detail and in lucid terms for a beginner to grasp their meaning, function, and differences easily.
Without going too far, it is worth noting that the first use of IMAP goes as far back as 1986. It was designed by Mark Crispin simply for retrieving the emails from servers. But POP protocol for similar purpose came even before that.
So, first: What is POP Protocol?
Simply put, when you use a software/client like Outlook to manage your emails, the client has to communicate to the server where your emails are stored. POP was one of the first and widely adopted protocol to facilitate that communication between a client and a mailbox server.

POP3 is the most latest version of the protocol that is being used currently, albeit, not by many (replaced by IMAP).
Short for ‘Post Office Protocol,” it was initially used to download an email from the server to the client and then deleting it from the server. However, it can also be configured to keep the original email on servers after downloading.
You can also set it up to download emails till the specified date. And also, set how frequently to look for and download new mails.
The workflow of POP3 is simple, which made it at the time the most common and a successfully system to retrieve emails: contact server à get all data à download locally on the computer à remove mail from server (or not, depending on your settings).
But the drawback of POP3 when compared to more modern IMAP protocol is that it does not sync the emails and the chances with the servers. Any changes you make locally on your client do not reflect back to the servers. It was fine on the PC as users often worked from one place.
But this became a major drawback after the mobile devices allowed users to access internet from anywhere. And therefore, IMAP became more common and useful.
What is IMAP Protocol?
In simple terms, it is very much like POP3 in the sense that it contacts the server and downloads the emails locally. But it is also more complex, allowing for better functionality and productivity to users.

The major purpose of IMAP is to allow complete control over their emails through email clients like Outlook and from anywhere. Which means, you can access your emails on Outlook or Apple Mail or any other client, and also, from a web-based interface (like Gmail) and get the same data everywhere.
This was made possible by making the communication between mailbox servers and clients a two-way street: so, the changes you make on your clients synchronizations in real time with the actual servers and back.

IMAP and POP – the differences
The two major and obvious differences between IMAP and POP (and how IMAP is far more desirable in many cases) are:
- Keep the data in sync
- Use multiple clients from any location and get access to the same database
But IMAP have a lot more benefits than those two, allowing to work with emails in a more sophisticated and efficient ways:
- IMAP allows you to download parts of emails separately (through MIME format). Ex: you can download the text and not attachments, or only headers, and so on.
- IMAP allows synchronization of flags, such as read and unread status, deleted, replied to, etc., both system flags and client defined flags.
- IMAP allows the use of folders, while POP3 downloads every email without the folders.
There are few shortcomings of IMAP protocol too:
- IMAP is more complex, so it needs more time to setup
- It consumes a large amount of internet bandwidth. Often, it is required because of the way it works, but at times, it can be unnecessary and can only be fixed by carefully implementing the settings, which can be difficult for a basic user.
- Sent emails need transmission two times (one for delivery and one for saving to your ‘sent’ folder)
- The added complexity can sometimes result in errors, unless properly configured.
- Even though there are “offline” modes now in modern email clients, IMAP is more suited originally for those who have constant internet.
- Depending on the settings, IMAP may only download headers, which means you cannot read those emails offline until you specifically download the contents as well.
Which one should you use – IMAP or POP3?
It depends on what you need, but in most cases today, IMAP protocol is often much better than POP3. The main reason is that many users likely access their emails from multiple machines: Home computer, Office computer, Smartphones, and laptops. With POP3 implementation, it could be exhausting to make sense of your emails. To always be in sync and neatly organized, IMAP is the best choice.
If you do not have fast and steady internet connection, it is okay to retrieve emails using POP3 and remove them from the servers. It is preferred if your task is often to read the contents and not do much changes to them.
POP also simplifies the workflow as it keeps all emails under one inbox. So, it may be better for users without too intense and demanding workflow. Hopefully, you can work out what is best for you. IMAP is more modern and widely used in comparison of POP. And if you do not have some special and unique case, go with IMAP. Most email accounts like Gmail and Microsoft support IMAP officially, and they work like popular clients like Outlook or Apple Mail right out the box.