Computer Basics by DigitalUnite and A Learner's Guide to the Computer by GrassRootsDesign are good computer guides for beginners. Whereas Computers Basics focuses on operating systems and user experience, the guide by GrassRootsDesign explains the technical sides of computers in simple terms.
The lessons in Computer Basics are divided into categories, which learners can view in any order and skip as desired. In comparison, A Learner's Guide to the Computer is presented as a series of lessons, and learners may not view lessons out of order.
DigitalUnite also offers brief guides on more advanced functions of computers, including Skype, social networking, blogs and Internet security.