POP was originally created to download copies of emails for offline use. The first version of POP was created in 1984, with POP2 created in 1985. POP3 is the latest version of the Post Office Protocol (POP), first introduced in 1988, and is used to collect email messages from a mail server that then go to a mail client. POP3 also deletes copies of the messages stored on the server, and then disconnects. Once the emails are deleted, the user cannot log on from any other device or client and see those emails, they can only be viewed in the original mail client because that is where they are downloaded to.