If POP is left to its default settings, each device using POP may end up with differences in their email. If another device accesses the email, it will not have access to the email that was downloaded on the previous device. This leaves the only copy of the new email on the device. By default, once the email account is accessed from another device, the server immediately hands the new emails over and deletes them on their end. Only incoming emails are stored on the server. The majority of emails using POP are stored on the user's machine. POP works well for single, dedicated devices with spotty internet connection because, while IMAP 'syncs' data between multiple devices, POP does not. However, with the modern, 'always-on' internet connections, this functionality is rarely needed anymore. The mail was stored on your computer instead of on the server so that you could read and respond while you were not connected to the internet. POP (Post Office Protocol) was built for dial-up connections. In short, the changes you make to your email client on one device will still be in place when you access the email client from another device. Any device that accesses an email client using IMAP will get the most recent iteration of the email mailbox. Essentially, emails are 'synced' across devices.

the new changes will be uploaded to the server. If you make changes to the email - whether deleting it, sending a new email, etc. The device then downloads it and lets you interact with the email. When a device accesses the email account, the server will pull the up-to-date information for the device. It does this by keeping email data stored on a server, instead of the user's machine. IMAP, short for Internet Message Access Protocol, allows access to email from many different devices. While they serve the same purpose, there are some striking differences between them. Email clients use both to manage emails and folders. Two common email protocols are IMAP and POP. Choosing an email protocol is part of setting up an email client.

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