I can't post a link now, but i think it has less programs (Student) student only has Word, Excel, PowerPoint, as far as i know... maybe a few more, later i can post a link with the differences.
The student version has Word, Excel, Powerpoint and OneNote, while the pro version has Access, Accounting Express, Excel, Outlook, PowerPoint, Publisher and Word.
If I recall correctly, the licence agreement for Home and Student edition prohibits commercial use, whereas the more expensive version has no such limitations.