What is the difference between a 15a and 20a outlet?

There are different pin configurations for 15a and 20a receptacles. A 20a receptacle has one slot that is turned sideways or T shaped to allow a 20amp plug to be used. A 15amp receptacle won't overload the circuit. Only 15a devices will be allowed to be plugged in.The 15 and 20 container has different pin configurations. A 20 container will have a slot that rotates sideways or as a T to allow the use of a 20amp connector. A 15amp container in a 20a circuit will not overload the circuit. Only 15a devices will be allowed to be connected.