Pages and Extents

The fundamental unit of data storage in Microsoft® SQL Server™ is the page. In SQL Server 2000, the page size is 8 KB. This means SQL Server 2000 databases have 128 pages per megabyte.

The start of each page is a 96-byte header used to store system information, such as the type of page, the amount of free space on the page, and the object ID of the object owning the page.

http://technet.microsoft.com/en-us/library/aa174529%28v=sql.80%29.aspx