Volume License key (VLK) is a term use by some computer software companies to denote the product key used when installing software licensed under volume licensing, which allows a single product key to be used for multiple installations. This form of licensing is typically used in business, government, and educational institutions, with prices for volume licensing varying depending on the type, quantity and applicable subscription term. For example, Microsoft software available through volume licensing programs includes Windows Vista, Windows Server 2008, Microsoft Office 2007 and many others.