If you've ever pet a cat you know they can love to be pet one minute, and then be swiping at you the next. It turns out we might not really be petting them correctly. Part of the issue is our modern cats have genetics very similar to those of their wildcat ancestors, so their brains are still wired to think like them. Wildcats live solitary lives, and don't really communicate in a social manner, while humans are an inherently social species. So to pet a cat properly you must first give the animal the choice to indicate whether or not they even want to be touched, let them indicated where they want to be pet, and for how long they want to be pet. Also, it's important to pay attention and see if the cat you're petting is comfortable. In general, most cats like being touched around the regions where their facial glands are located, including the base of their ears, under the chin, and around their cheeks. These areas are usually preferred over areas such as their stomach, back, and base of their tail.
(Yahoo)