Liability car insurance is a type of auto insurance coverage that provides financial protection for the policyholder in case they are responsible for causing an accident that results in injuries or property damage to others. 

This type of insurance does not cover the policyholder's own injuries or vehicle damage but rather the costs incurred by others involved in the accident.

Liability insurance typically includes two main components:

Bodily Injury Liability: This part of the insurance policy covers the medical expenses, rehabilitation costs, and potential legal expenses for individuals who are injured or killed in an accident for which the insured driver is at fault. It may also cover the policyholder's legal defense costs in case they are sued.

Property Damage Liability: This component covers the costs associated with damage to someone else's property, such as their vehicle, home, or other personal belongings, that is caused by the insured driver in an accident.

Liability insurance is typically expressed in terms of coverage limits, such as 250/500/300, where:

The first number (e.g., 250) represents the maximum amount in thousands of dollars  the insurance company will pay for bodily injury per person.  ($250,000)

The second number (e.g., 500) represents the maximum amount in thousands of dollars the insurance company will pay for bodily injury per accident.  ($500,000)

The third number (e.g., 300) represents the maximum amount in thousands of dollars the insurance company will pay for property damage per accident.  ($300,000)

These limits may vary depending on state requirements and the policyholder's preferences. It's important to choose liability coverage limits that provide adequate protection based on your assets and potential risks.

In most places, liability car insurance is mandatory, and drivers are required to have a minimum level of coverage to legally operate a vehicle. The purpose of liability insurance is to protect both the policyholder and the people involved in an accident by ensuring that there is financial coverage to pay for damages and injuries.