If you are looking to enhance the coverage you already enjoy from health insurance, you might want to consider buying critical illness insurance. Critical illness insurance covers you against dread diseases like stroke and cancer by offering you a lump sum payout if you are diagnosed with these diseases. This might make you wonder – what does cancer insurance do? Should you get coverage against cancer through critical illness insurance or with a cancer-specific plan? Are there any major differences in the coverage offered by these two plans?