Critical illness cover is designed to pay out a lump sum if you get a serious illness or suffer traumatic life-changing injury. The illnesses covered vary from one insurer to the next, but cancer, stroke, heart attack and multiple sclerosis will be included.
This cover isn't built into your life insurance policy. Life insurance is intended to pay out when you die, or if you're diagnosed with a terminal illness where you're likely to die in the near future (usually within 12 months). Critical illness cover covers you for serious illnesses from which you may recover.