A liability is an obligation and it is reported on a company's balance sheet. A common example of a liability is accounts payable. Accounts payable arise when a company purchases goods or services on credit from a supplier. When the company pays the supplier, the company's accounts payable is reduced.
Other common examples of liabilities include loans payable, bonds payable, interest payable, wages payable, and income taxes payable. Less common liabilities are customer deposits and deferred revenues. Deferred revenues come about when customers prepay a company for work to be done in a future accounting period. When the company performs the work, the liability will be reduced and the company will report the amount it earned as revenues on its income statement.
Liabilities are also part of the accounting equation: Assets = Liabilities + Stockholders' Equity. Liabilities are often viewed as claims on a company's assets. However, liabilities can also be thought of as a source of a company's assets.