During your lifetime you have certain financial goals. Life insurance is a way to achieve those goals for those you leave behind. If you are in debt, life insurance is used to protect the person you are indebted to. If you are a key person in a company, your loss could mean a real financial loss to that company.
Life insurance insures that potential loss.
If you are a partner in a business, if you were to die, life insurance allows the partner to buy your share of the business from your heirs. Life insurance could help pay estate taxes. If you have a favorite charity, life insurance can help you give to that charity after you are gone. If you have less than is needed, your dependents won't be able to replace the income you are currently making. Once you have decided on the amount of coverage needed then you should shop the market on what product to purchase.