What is a tablet PC?

A tablet PC is sort of a PDA/laptop hybrid. It looks like a laptop, but has a display that you can write directly on, usually with a special pen called a stylus, although some models let you write with your finger, too. Using a pen or finger—as opposed to a keyboard and mouse—tablets make it easy to draw diagrams and pictures, take quick notes, and navigate menus, websites, and other documents.

Slate tablets lack a keyboard altogether, while convertible tablets have a display that swivels and folds over the keyboard.

For many years, tablet PCs were used mostly by small niches of professionals including doctors, architects, and engineers—that is, people who worked on their feet, needed to take quick notes or draw diagrams, or engaged in other tasks that didn’t necessarily lend themselves easily to keyboards. Tablets continue to gain acceptance (slowly) from the mainstream, and some consumer laptops now have some tablet functionality built in.

Leading tablet PC manufacturers include Lenovo, Fujitsu, Gateway, HP, and Toshiba; click here for a more complete list of vendors. Microsoft, which makes a special version of Windows for tablets and has been pushing the form-factor for a number of years, hosts a Website that offers more information.

Justin Jaffe, the author of CNET Do-It-Yourself Laptop Projects: 24 Cool Things You Didn't Know You Could Do!, is a writer and technology expert in Portland, Maine.