Dual in-line package
A dual in-line package is one way of making microchips and other integrated circuits. The circuit is put inside of a container made out of materials such as plastic or ceramic. All the wires of the circuit are connected to metal pins, and they stick out of the package on two sides. This way the circuit is able to be used from inside the package.
Things can also be put in a dual in-line package that are not integrated circuits. A DIP switch is one example of this, where there are switches on top of the package instead of a circuit inside.