Is Null condition in SQL Server

This is IS NULL condition is the only condition that directly tests for nulls. Null value is not considered to be greater than,equal to, or less than NULL. Even a space is not considered to be a NULL, and a null is not considered to be a space. Nulls are not considered like any other value in a table either, since nulls do not have data types. Also, because nulls do not have data types, there is no distinction between nulls in numeric columns and nulls in text columns or date columns.

The is null operator returns TRUE if the operand or result set has a NULL value.