What is the name of the latest material that is used to build airplane structure?

Carbon Composites is the correct answer - carbon fiber reinforced polymer (CFRP) composites represent the latest advancement in aircraft construction, offering superior strength-to-weight ratio compared to aluminum. Modern aircraft like the Boeing 787 Dreamliner and Airbus A350 use extensive carbon composite structures. Titanium is also used but primarily for specific high-stress components like landing gear and engine parts.