The Arduino Prototyping Shield makes it easy for you to design custom circuits. You can solder parts to the prototyping area to create your project,or use it with a small solderless breadboard (not included) to quickly test circuit ideas without having to solder. It's got extra connections for all of the Arduino MEGA I/O pins, and it's got space to mount through-hole and surface mount integrated circuits. It's a convenient way to make your custom Arduino circuit into a single module.