Boeing builds nearly anything you can imagine, but what they're best known for is their commercial jet business. I worked in their Flight Controls PD (Product Development) department, on projects meant for airplanes ten years or so away. This mostly means that I can't talk about most of what I did there, but I can say that I was working on next generation aircraft wings. Boeing's main focus when building aircraft today is efficiency. Specifically, how much fuel do you burn per seat during each flight. The lower this ratio is, the better it can sell it's airplanes against it's competitors like Airbus. Much of what I learned while I was there was the design of aircraft systems that would not only be safe, but fit into and aerodynamic envelope, and be light enought to be a good value proposition to Boeing and it's customers.