bird's-eye view
1. Lit. a view seen from high above. We got a bird's-eye view of Cleveland as the plane began its descent. From the top of the church tower you get a splendid bird's-eye view of the village.
2. Fig. a brief survey of something; a hasty look at something. The course provides a bird's-eye view of the works of Mozart, but it doesn't deal with them in enough detail for your purpose. All you need is a bird's-eye view of the events of World War II to pass the test.