T-SQL: Comparing Two Tables - Records that don't exist in second table

Question

If UNION ALL is an addition in T-SQL. What is the equivalent of subtraction?

For example, if I have a table PEOPLE and a table

Answer 1

SELECT * FROM Table1
WHERE Table1.Key NOT IN (SELECT Table2.Key FROM Table2 WHERE Table2.Key IS NOT NULL)

Added IS NOT NULL to make people happy.

I would agree with Tom. His version is most likely more efficient. The only possible reason to use mine, might be that it's prettier.