Cozumel is one of the biggest Islands of Mexico and the biggest in the Caribbean. Cozumel is worldwide known as a meca for divers, it is full of marine life and caves you can visit. It is also very well known because it's a main destination for Cruise ships.
Cozumel is a laid back island with everything you may need in a vacation. You can find small friendly hotels to All Inclusive Resorts. In the whole island you'll find restaurants and bars you can go to spend some time with your family or friends.
Cozumel has its own airport but Cancun Airport has a lot more flights from all around the globe, that's why lots of people fly down to Cancun to then go to Cozumel by ferry from Playa del Carmen.
If you are wondering how to get to Cozumel from the Cancun Airport you better check out: Cancun Airport to Cozumel