The Airbus A320neo is the new-engine version of the A320 family, launched in 2010 and entering service with Lufthansa in 2016. The letters 'neo' stand for New Engine Option, and the change is exactly that: the A320neo uses larger, more efficient engines than the ceo and incorporates aerodynamic refinements including sharklet winglets that come standard. The fuel savings compared to the ceo are approximately 15 to 20 percent, which has made the neo extremely popular with low-cost carriers and network airlines alike. Airbus has orders in the thousands. The neo is visually very similar to the ceo, but you can usually spot it by the slightly larger engines and the absence of wingtip fences on newer aircraft in favor of sharklets. It is now the single best-selling commercial aircraft in the world by order backlog.