Functional programming has its roots in lambda calculus, a formal system developed in the 1930s to investigate computability, the Entscheidungsproblem, function definition, function application, and recursion. Many functional programming languages can be viewed as elaborations on the lambda calculus.
The sternum or breastbone is a long flat bone shaped like a necktie located in the center of the chest. It connects to the ribs via cartilage, forming the front of the rib cage, and thus helps to protect the heart, lungs, and major blood vessels from injury. The sternum consists of three regions: the manubrium, the body, and the xiphoid process.
The shape of the sternum looks somewhat like a sword pointing downwards, with the manubrium forming the handle, the body forming the blade, and the xiphoid process forming the tip. The manubrium is the widest and most superior region of the sternum.