Re: urgent help
HTTP = One of the web protocols (web browsers use this). HTTPS is another
POP3 & IMAP (not AMAP) = These are some protocols used by email
For Yahoo you would use HTTP (non secure) or HTTPS (secure) protocols.
If you have the Yahoo Pro version (paid) it allows you to use POP3 (not sure if they provide IMAP). To use this you would use an email client (e.g. Outlook Express) and it would let you download your emails to your local computer. You can also configure your GMail account to retrieve all your Yahoo mail so you can see all of them in one place.
Hope I didn’t overshoot the question and it covers what you were asking.