What is the difference between clustered and a non-clustered index?

What is the difference between clustered and a non-clustered index?

A clustered index is a special type of index that reorders the way records in the table are physically
stored. Therefore table can have only one clustered index. The leaf nodes of a clustered index contain
the data pages.
A nonclustered index is a special type of index in which the logical order of the index does not match
the physical stored order of the rows on disk. The leaf node of a nonclustered index does not consist of
the data pages. Instead, the leaf nodes contain index rows.

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