With the release of firmware 1.1.3, the first-generation iPhone knows where you are. At least, it can figure it out.
This is extremely helpful in using the phone to get driving directions and real-time traffic information. The feature does employ a GPS (global positioning system). While GPS is more accurate — the iPhone is only accurate to within a few hundred feet, while GPS is generally accurate to within a few feet — it would also require bulkier hardware and more battery life.
Triangulation, Not GPS
Instead of using GPS, the iPhone uses a technique called triangulation to determine where it is. This is done by bouncing a signal off three cellphone towers near the phone. By measuring the three responses, it’s possible to roughly pinpoint the location of the phone that’s sending the signal — and thus give you the location-specific information you need.

