Corral is a puzzle type originally created by Nikoli.
Shade cells so that all unshaded cells are connected, and shaded cells are not enclosed by unshaded cells (They must be connected to a wall). All numbered cells are unshaded, and the number indicates the amount of unshaded cells that are orthogonally visible to the numbered cell including itself.
See this example puzzle and its only solution.
Jamie's Deceptive Puzzles 