It’s great for users who only want to access their mail from one client. Pop3 downloads your mail as you view it on your email client. Pop3 stands for Post Office Protocol and has been around for many years. These clients include Microsoft Outlook or Mozilla Thunderbird, a mobile device such as a smartphone or tablet or an online webmail interface such as Gmail, or 123-mail. Pop3 and IMAP are protocols used to connect your mailbox server to an email client. To start, let’s learn exactly what Pop3 and IMAP are. Hi there, in this video we will demonstrate the differences between Pop3 and IMAP email protocols and help you decide which one to use.