Nice question, but the explanation lacks important information. Let me quote it for you here:
Table Hints (Transact-SQL) - SQL Server 2008 R2
WITH ( <table_hint> ) [ [ , ]...n ]With some exceptions, table hints are supported only when the hints are specified with the WITH keyword. Parentheses are required.
Important note
Important
Omitting the WITH keyword is a deprecated feature and will be removed in a future version of Microsoft SQL Server. Always specify WITH in new development work, and modify applications that currently omit this keyword.
Separating hints by spaces instead of commas is a deprecated feature and will be removed in a future version of Microsoft SQL Server. Always specify commas in new development work, and modify applications that currently omit commas.
The following table hints are allowed with and without the WITH keyword: NOLOCK, READUNCOMMITTED, UPDLOCK, REPEATABLEREAD, SERIALIZABLE, READCOMMITTED, FASTFIRSTROW, TABLOCK, TABLOCKX, PAGLOCK, ROWLOCK, NOWAIT, READPAST, XLOCK, and NOEXPAND. When these table hints are specified without the WITH keyword, the hints should be specified alone. For example, FROM t WITH (TABLOCK). When the hint is specified with another option, the hint must be specified with the WITH keyword. For example, FROM t WITH (TABLOCK, INDEX(myindex)).
The restrictions apply when the hints are used in queries against databases with the compatibility level of 90 and higher.
http://msdn.microsoft.com/en-us/library/ms187373%28v=sql.105%29.aspx
If you are working with a different SQL Server version, be sure to read the corresponding documentation version as well.
Best Regards,
Chris Büttner