Boats typically have several metal fittings where ropes can be fastened. What is the name for these metal fittings?

The name for these metal fittings is cleats.

Cleats refer to the hooks on your boat and the dock where you can fasten a boat in order to keep it from flowing away while you're not using it. A keel is located under your boat and provides stability; a transom is the part of your boat on the stern where the motor is located; a tiller is a lever you use to turn your boat.