What's the difference between a Table Scan and a Clustered Index Scan?

Question

Since both a Table Scan and a Clustered Index Scan essentially scan all records in the table, why is a Clustered Index Scan supposedly better?

Answer 1

A table scan has to examine every single row of the table. The clustered index scan only needs to scan the index. It doesn't scan every record in the table. That's the point, really, of indices.