The location services feature on your iPhone allows location-based apps (like Maps, Yelp, Camera, etc.) and websites to determine your location based on information from GPS, Wi-Fi, cellular and iBeacon networks. If you have location services enabled, your iPhone will keep track of places you have been, when you were there and how often you've been there. If you want to see this information, here is how you do it in iOS 7:
1. Go to Settings -> Privacy -> Location Services.
2. Scroll all the way down and go to "System Services."