Map of Cancun Airport
Here's a map of Cancun airport. The map shows the terminal buildings upon opening of Terminal 3 in May 2007.
Terminal 1 was devastated after Hurricane Wilma, once repaired it was brought back into operation on a periodic basis pending the completion of Terminal 3. During this time Terminal 2 dealt with the vast majority of arrivals which resulted in overcrowding. With the opening of T3, dealing with the majority of charter flights Cancun airport is a much more pleasurable experience than in previous years.
Now Cancun Terminal 3 is fully operational, the first terminal and all it's antiquities (lack of air conditioning, sparse retail outlets and restaurants) is expected to be "retired".