Checks are negotiable instruments asking a bank to pay a specific amount of money from a specific account to a bearer or payee. The account is ideally in the depositors name with the bank. The depositor or check maker and the payee can be either natural persons or legal entities. A check must contain all the features to be considered valid. Check number, account number, MICR, date of issue, payee, amount of currency, and signature of drawer are the basic pre-requisites of a check. A check is usually valid for six months after the issue date unless indicated otherwise. However, the validity may vary in different countries.

Checks come in several types. In the U.S., checks are regulated by the Uniform Commercial Code, Article 3. Two very common types of checks are order checks and bearer checks. An order check is payable only to the named payee or his endorsee. It begins with Pay to the order of. A bearer check is payable to anyone who is in possession of the document. Such a check usually does not specify a payee and is payable to bearer or To the order of cash. This type of check is payable to someone who is not a person or legal entity. When checks are drawn from savings and loan association, they are called negotiable order of withdrawal. If checks are cashed from a credit union, they become share drafts.

Checks are used to pay wages also. Such instruments are referred to as payroll checks. A check sold by a post office or merchant such as a grocery for payment by a third party for a customer is called postal order or money order. If a check allows the person signing it to make an unconditional payment to someone as a result of paying the account holder for that privilege, it is referred to as a travelers check. Such a check can be replaced in case of theft or loss and are very popular with travelers.