What do Clustered and Non clustered index actually mean?

Question

I have a limited exposure to DB and have only used DB as an application programmer. I want to know about Clustered and Non clustered indexes. I goo

Answer 1

Find below some characteristics of clustered and non-clustered indexes:

Clustered Indexes

1. Clustered indexes are indexes that uniquely identify the rows in an SQL table.
2. Every table can have exactly one clustered index.
3. You can create a clustered index that covers more than one column. For example: create Index index_name(col1, col2, col.....).
4. By default, a column with a primary key already has a clustered index.

Non-clustered Indexes

1. Non-clustered indexes are like simple indexes. They are just used for fast retrieval of data. Not sure to have unique data.