What is the practical difference between the peninsula and bridge on a U-shaped desk?

The peninsula is the return section that connects the two parallel desk surfaces, running perpendicular to both — it's the "cross" of the U. The bridge is sometimes used as a synonym but more specifically refers to an overhead unit bridging two surface sections. In most commercial U-desk catalogs, the "bridge" is the horizontal connector work surface, and the "credenza" or "return" is the long parallel section on the opposite side from the main desk. FindOfficeFurniture.com can walk you through exact component terminology — call 888-719-4960.