Boeing Commercial Airplanes - Wikipedia
https://en.wikipedia.org/wiki/Boeing_Commercial_AirplanesFor all models sold beginning with the Boeing 707 in 1957, except the Boeing 720, Boeing's naming system for commercial airliners has taken the form of 7X7 (X representing a number). All model designations from 707 through 787 have been assigned, leaving 797 as the only 7X7 model name not assigned to a product. For models 707 to 777, the full model number consists of an airplane's model …
Boeing: 777X
https://www.boeing.com/commercial/777xThe new Boeing 777X will be the world’s largest and most efficient twin-engine jet, unmatched in every aspect of performance. With new breakthroughs in aerodynamics and engines, the 777X will deliver 10 percent lower fuel use and emissions and 10 percent lower operating costs than the competition. A true family, the 777X offers low-risk ...