SQL Server Binary and Large-Value Data (ADO.NET)
Microsoft SQL Server 2005 introduced the max specifier, which expands the storage capacity of the varchar, nvarchar, and varbinary data types. varchar(max), nvarchar(max), and varbinary(max) are collectively called large-value data types. You can use the large-value data types to store up to 2^31-1 bytes of data. The text, ntext, and image data types in earlier versions of SQL Server can be replaced with varchar(max) and nvarchar(max), respectively, and the image data type can be replaced with varbinary(max).
With large-value data types you can work with SQL Server in a way that was not possible using earlier versions of SQL Server, where binary large object (BLOB) data requires special handling.
SQL Server 2008 introduces the FILESTREAM attribute, which is not a data type, but rather an attribute that can be defined on a column, allowing large-value data to be stored on the file system instead of in the database.