There are also a series of lights (red, blue, and ???) that indicate what the ding means. I believe that blue off is "sterile cockpit" or the 10,000 foot ding. Red means the cockpit is on the phone. ??? is a passenger call button. For the life of me I can't remember the colors, but it probably varies by airline/aircraft.

Double ding means short final and last call to get the cabin ready for landing.

ding ding ding ding ding ding ding ding ding ding ding ding ding ding ding ding ding ding ding ding ding ding ding ding ding ding ding ding ding ding ding ding ding ding ding ding ding ding ding ding ding ding ding ding ding ding ding ding ding ding..... means 200 passengers are trying to operate the IFE remote and are hitting the call button by mistake.