Adding IMAP email on your iPhone
This article was originally written in 2005 as a support forum article. This is still relevant today so I have decided to add and update it here for posterity.
If you are looking to take advantage of IMAP ability to sync your emails across mutiple devices such as your mobile phone or pda, while being able to also pick them up from your home or work computer, them IMAP is the way to go.