SMTP (Simple Mail Transfer Protocol) and IMAP (Internet Message Access Protocol) are the two protocols used to send and receive email messages (Internet Access Message Protocol). The primary distinction between the two is their function. SMTP is the protocol used to send email from a client or between servers for delivery to the intended recipient. IMAP, on the other hand, is a protocol that allows you to manage and retrieve email messages from a server. So, even if you aren't aware of it, if you use email, you are most likely using both protocols.

Another significant distinction between SMTP and IMAP is their application. IMAP is only used between the client and the server when retrieving emails. Clients use SMTP to send emails to servers, but servers also use it to push emails to other servers, which is especially important when the sender and recipient do not subscribe to the same service provider.

POP3 is another email retrieval protocol, in addition to IMAP. These are the two most widely used email retrieval protocols, with IMAP being the more powerful. POP3 is still widely used today because it was previously supported in older devices.

SMTP is without a doubt the most widely used email protocol. Although there are other email outgoing protocols, SMTP is the most well-known and widely used.

When using browser-based email services, there is no need to fiddle with or even know the protocol being used or the exact addresses used for these protocols. These details are only relevant if you send and receive emails using a different client, such as Microsoft Outlook or Mozilla Thunderbird. You may be able to obtain two relevant addresses, depending on your service provider: one for SMTP and one for either IMAP or POP3. If these addresses are not properly configured in your client, you will be unable to receive, send, or both.

1.SMTP is used for email transmission, whereas IMAP is used for email retrieval.

2.SMTP is used to communicate between servers, whereas IMAP is only used between the client and the server.

3.SMTP is the most widely used protocol for sending email, while IMAP is only one of two widely used protocols for retrieving email.