What is the difference between Where and Having Clause?

Where Clause	Having Clause
WHERE clause can be used without GROUP BY clause.	HAVING is typically used in a GROUP BY clause. When GROUP BY is not used, HAVING behaves like a WHERE clause.
WHERE clause can not contain aggregate functions.	HAVING clause can contain aggregate functions.
WHERE clause can operate individual row.	HAVING clause can operate group of row.
It is more fast.	It is much slow.
WHERE clause select rows before grouping.	HAVING clause select rows after grouping

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