Liability insurance insures against liability legally imposed upon your business because of the negligence of the business or its employees. Put another way, it protects your business when the business is sued for negligence.
Your personal automobile policy does NOT cover vehicles used by your business. If your business uses vehicles or anything that is required to be titled by your state, then you need a commercial auto policy. Commercial auto coverage insures against property damage to vehicles and damage caused to others by those vehicles.
You will need to insure your employees against on-the-job injuries. Every state is different. But, most states have put into place some form of workers' compensation system. Workers' compensation is a system where the employee is not allowed, by statute, to sue their employer for on-the-job injuries; but, in return, the employer must participate in a system that provides nearly automatic payment to the employee in case of injury for medical bills and damages. There are many options for workers' compensation coverage. Some states allow an employer to opt-out of the system if the employer is self insured, some run the system through private insurers while others use state agencies.
Business interruption insurance insures against loss or damage to the cash flow and profit of a business caused by the business being unable to operate because of interruption. The easiest example is to think about a critical piece of machinery being struck by lightning. The repairs to the machine may be covered by other coverage such as property or casualty insurance. But, if you can not make widgets for three months, than there is no replacement of that income without this coverage.
Property insurance insures against loss or damage to the location of the business and its contents. It can also insure the property of others in your control when the loss occurs. Property insurance can be for a specific risk. For example, a fire insurance policy insures only against a fire loss to the location. A tornado is not a fire and, therefore, that loss would not be covered. The insured location can be owned, leased or rented.
Some insurers will lump property and casualty insurance together and refer to the coverage as property and casualty insurance. In fact, packaged policies of property and casualty are often the best purchase a business owner can make. However, to have an understanding of the difference between the coverage, I will discuss this as a separate type of insurance. Casualty insurance insures against loss or damage to the business.