Procedure

A procedure is a subprogram that performs a specific action

Procedure Does and Does not return the Value.

Procedure we can use (In, Out, InOut Parameter)

You cannot use the procedure in select Statement.

Execute as a PL/SQL statement

No RETURN clause in the header

Can return none, one, or many values

Function

A function is a subprogram that computes a value

Invoke as part of an expression

Must contain a RETURN clause in the header

Must return a single value

Must contain at least one RETURN statement

Always return the Value.

Function you cannot use the (In, Out, InOut Parameter)

You can use the Function the in select Statement.