Polling or Interrupt based method

Question

When should one use polling method and when should one use interrupt based method ? Are there scenarios in which both can be used ?

Answer 1

Polling should be avoided where possible, as it typically eats a lot of CPU cycles unnecessarily (unless either (a) you are only going to poll for a short time or (b) you can afford to sleep for a reasonable time in your polling loop). Wasting CPU cycles is bad not only from a performance perspective, but it also drives up power consumption, which may well be an issue for battery-powered embedded applications.