Ans: Third-party insurance offers protection against damages to the third-party by the insured vehicle. It covers physical injuries, damages to the vehicle, damage to the property, and death for the affected third party.
Comprehensive insurance covers all the benefits of third-party insurance, and also provides the additional benefits of own damages sustained by your car which includes road accidents, fire, natural calamity, etc.
Zero depreciation is an add-on cover that you can choose for your car insurance as per your requirement. You won't have to pay for depreciation during your car insurance policy claims if you have a zero depreciation add-on cover. You'll save a lot of money in the long term by paying a slightly higher premium.