Is Phukets main tourist area and offers almost everything that is found in Phuket city. Patong Beach has a nice beach with lot of beach chairs and shops facing the beach. The night entertainment here is so active that you wont find any similar nightlife anywhere else on the island. It is a place that I do not recommend for families, definitely not at night time. A big shopping mall (Jungcylone) with restaurant, food yards and all kind of stuff to spend money on.
Is one of the most family friendly beaches on the island with a nice scenery of green hills facing the beach and two nice reefs for snorkeling or even SCUBA diving. Kata Beach is like Patong but in much smaller scale for restaurants, bars, karaoke, hotels, massage and spas.
Is the second largest tourist area after Patong Beach, and it has the longest beach on the whole island. Like in other tourist areas, you will find a variety of restaurants, hotels, bars, karaoke and massage. During the high season and specially over Christmas, Karon is invaded by Scandinavian tourists.
There are lot of other beaches on the island. Some are more quiet, some are less quiet than Kata beach. Some are private or can only be accessed from the hotel! Have a look at the map or read more about Phuket to find more details about the beaches.