Blackout curtains are a type of window covering that can block out most or all of the light from outside. They are usually made of thick, lined fabric that prevents sunlight and artificial light from passing through. Blackout curtains can help you sleep better by creating a dark and comfortable environment in your bedroom. They can also reduce your energy costs by keeping your room cooler in the summer and warmer in the winter. Blackout curtains can also provide more privacy and noise reduction for your home.