Robot Operating System (ROS) is a collection of software frameworks for robot software development, providing operating system-like functionality on a heterogeneous computer cluster.
If you've ever wondered how to control the headlight of a car from a microcontroller, a MOSFET is what you need. The FQP27P06 is a very common MOSFET with very low on-resistance and a control voltage (aka gate voltage) that is compatible with most 5V microcontroller or mechanical switches. This allows you to control high-power devices with very low-power control mechanisms.