Email gets transmitted amongst and between servers and ends up in your inbox through one of two processes: POP3(Post Office Protocol version 3) or IMAP (Internet Messaging Access Protocol). While you may have seen either of these two terms before when setting up mail on a a new device, we’ll break down for you exactly what is happening with these two distinct actions.

POP3, which was the first of the two, downloads information from the server onto your personal computer and subsequently deletes the data from the server. POP3 does not require a constant connection while you read email. Though this process is great at conserving space on your server, it makes it pretty difficult to access your data across multiple devices.

Inversely, while IMAP requires significantly more disk space on your machine than POP3, this process also provides increased flexibility when it comes to accessing your email across devices. IMAP leaves information on the server and synchronizes read and unread messages, folders, and spam across any device in which you’d access your email.

While this method is more convenient than POP3, this method generally requires more dedicated disk space than POP3 because users tend not to delete old email. However, if the users monitor their disk usage and delete old messages when necessary, IMAP is still viable on a mail server with limited resources.

While IMAP has emerged as the leading method for mail delivery, both processes have their advantages and disadvantages. Carefully consider your system’s available resources before you choose a courier.