I am at Sheremetyevo International Airport in Moscow. A modern, interesting airport.
They are all the same, but still different. In fact aurports can be very different. The key functions are the same though. Basically the logistics of moving passangers in and out of airplanes as quick as possible. The things that are different are normally related to the extra services, namely; comfort, waiting space, shops and restaurants. My favourite airport is Schiphol in Amsterdam. In Asia I like Singapore Shangi International Airport, which is clearly one of the best in the world.