Lighting the outside of your home can help protect your property. Security flood lights make it harder for would-be intruders to sneak around in the shadows. Outdoor lights can also help you see where you're going when it's dark. Clearly lit walkways and paths can help keep you from tripping and falling at night.
Motion detection lights work well for when you need to keep the light down but you still need to monitor cases where someone might approach your property. Flood lights are best when you have larger areas to light up.