An options chain is an informational table which quotes all options in the same underline asset with different strike prices and the same expiration.
It contains all the information needed in order for someone to open a position i.e. strike price, expiration, last price, bid-ask, volume and open interest. More or less all trading platforms include almost the same information.
Below is an options chain from Yahoo.Finance for the stock NUAN. It includes all strike prices for calls and puts that expire on January 2014.