You probably hear the term "smartphone" tossed around a lot. But if you've ever wondered exactly what a smartphone is, well, you're not alone. How is a smartphone different than a cell phone, and what makes it so smart?

In a nutshell, a smartphone is a device that lets you make telephone calls, but also adds in features that, in the past, you would have found only on a personal digital assistant or a computer--such as the ability to send and receive e-mail and edit Office documents, for example.

But, to really understand what a smartphone is (and is not), we should start with a history lesson. In the beginning, there were cell phones and personal digital assistants (or PDAs). Cell phones were used for making calls--and not much else--while PDAs, like the Palm Pilot, were used as personal, portable organizers. A PDA could store your contact info and a to-do list, and could sync with your computer.

Eventually, PDAs gained wireless connectivity and were able to send and receive e-mail. Cell phones, meanwhile, gained messaging capabilities, too. PDAs then added cellular phone features, while cell phones added more PDA-like (and even computer-like) features. The result was the smartphone.