Venus, the second planet from the Sun, is perpetually veiled behind opaque clouds of sulfuric acid droplets atop a hot, heavy, carbon dioxide atmosphere. In size and apparent composition, however, it is a near twin-sister of the Earth. Why is it do different? In this lecture I review the basic properties of Venus, and examine the similarties and differences with the Earth. Recorded 2007 Nov 8 in 1000 McPherson Lab on the Columbus campus of The Ohio State University.