MySQL - what is subquery?

A subquery is a query that is nested inside statements (like SELECT , INSERT , UPDATE , DELETE) or inside another subquery.

It is used to return data that will be used in the main query as a condition to further restrict the data to be retrieved.

Practical example:

SELECT * FROM (
    SELECT * FROM `table_name` 
	ORDER BY `column_name` DESC
	LIMIT N
) subquery
ORDER BY `column_name` ASC;