The payment of wages is regulated by federal and state law. Employers must pay wages in cash or its equivalent, and direct deposit is continually gaining popularity as a convenient method for paying wages. In addition to the method of payment, state laws also regulate how frequently employees must be paid. Many states have laws regarding the payment of wages upon the termination of employment, including accrued vacation, and these rules often differ depending on whether the termination is voluntary or involuntary. State and federal laws also require that employers maintain certain records related to payroll.