Yes, it is regular smart card. You can buy in the airport and use it for express train. For the first time, you should pay at least 40 yuan, 20 yuan for returnable deposit and 20 yuan for you to use. If you want to use it pay the express train which costs 25 yuan, you need to prepay more money in the card. For every single time, you can put 10 yuan, 20 yuan, 30 yuan or more you want into it. Will deduct the exact fare from the card. You should make sure there are monry left in card. There are discounts on cuty bus, 60percent off. No discount on subway and express train. Beijing subway is cheap, only 2 yuan without limit on how many transfers you make within the subway stations. Tourist bus with 9 including 919 support payment by smart card. Here is the Chinese subway map:
http://www.bjsubway.com/cczn/dtxlt.asp
Wait Line 2 for every 3 minutes. 919 bus is easy to catch too. It has many branch lines.