Employee Retirement Income Security Act, which is also referred to as ERISA, is a federal law that makes sure that minimum criteria for employee plans like healthcare and pension are met and that the rights of these employees (covered by the plan) are protected.
ERISA puts certain responsibilities on people who manage these plans. Other than that, ERISA also requires certain information which is considered necessary to the participant to be provided. In short, ERISA works in the best interest of employees covered by different plans any may also assist them through an appeal process.