Outlook is the e-mail client that comes with Microsoft Office, which is free for download for Pomona students. It has some other cool features like a calendar, an address book, a to-do list, and so on. It's generally a good way for busy college students to attempt to stay organized.
How do I configure Outlook to check my Pomona e-mail?
ITS recommends that for general use, you set up Outlook to use Exchange. (Why Exchange?)