Clustered index and non clustered index in SQL

Clustered index which reordered the table and saved separately as index table(data pages stored as B-tree) there can be one clustered index per db & Non clustered index is typically a index(data pages stored as heap)

A table can have only one clustered index with many non clustered indexes.

The leaf nodes of the cluster index stores data pages and non clustered index stores key values(where as table includes clustered index) or rid's(table contains non cluster index only).