They can adjust the stiff feathers to funnel sound into their ears - a bit like cupping your hands behind your ears. They have incredibly sensitive hearing, and can even hear the sound of an earthworm burrowing through the soil. They perch and listen, and when they've located their prey they swoop down and grab it with their vicious talons. The soft fringes on their flight feathers mean they hardly make any noise as they fly. Owls don't hunt in the rain because the pitter-patter of raindrops on the forest floor stops them hearing properly.
Owls have very specialised eyesight so they can see in very low light levels.
Their eyes are probably 100 times more sensitive to light than ours. They have binocular vision like we do, which means their eyes face forward and they move their heads to see more. When an owl bobs about, or turns its head to one side or the other, it's actually getting different views of the world around it in order to pin-point where its prey is.