Insurance is a contract in which one party (the "insured") pays money (called a premium) and the other party promises to reimburse the first for certain types of losses (illness, property damage, or death) if they occur.
Insurance law is a law related to insurance which is made to protect the policies and claims of insurance which can be broken into categories. First, the insurance company will hire lawyers to represent the insured in case she is sued for something related to her insurance contract. These are known as "insurance defense attorneys. The second category of insurance law helps insured people to determine when an insurance company must pay a claim. Third, insurance companies typically hire attorneys to make sure the company complies with all applicable laws and regulations.
There are many types of insurance. The government runs some kinds of insurance, like Social Security disability, worker's compensation, and unemployment insurance. The most common types of private insurance are health insurance, homeowner's insurance, life insurance, title insurance, and malpractice insurance.
Since there are so many different types of insurance, and insurance touches so many aspects of life, most lawyers are familiar with some aspect of insurance law. Personal injury and medical malpractice attorneys routinely deal with medical insurance companies, similarly, auto accident attorneys routinely work with auto insurance companies. Real estate attorneys often recommend that their clients purchase title insurance, and are very familiar with homeowners' insurance policies. Probate attorneys must frequently distribute life insurance proceeds and estate planners often recommend different types of life insurance arrangements.