The July 2009 edition of TechNet Magazine is available on the web and include a feature article I wrote explaining backups. It's the first in a 3-part series, with parts 2 and 3 being on recovering from disasters using backups and recovering from disasters without backups.
The backup article covers:
Putting together a backup strategy
It debunks a lot of myths about backups, explains in detail how each backup works, and explains the pros and cons of some different backup strategies.
Check it out at Understanding SQL Server Backups – enjoy!
PPS I've just signed a contract with TechNet Magazine so that there will be something on SQL Server in every issue – either my SQL Q&A column or a feature article. Very cool!