Pin tumbler lock. A common type of pin tumbler lock, of the euro cylinder type. The pin tumbler lock (or Yale lock, after lock manufacturers Yale) is a lock mechanism that uses pins of varying lengths to prevent the lock from opening without the correct key.
noun. A person creating a diagram. A person creating a diagram. The definition of a diagram is a graph, chart, drawing or plan that explains something by showing how the parts relate to each other. An example of diagram is a chart showing how all the departments within an organization are related.
State diagram. A state diagram is a type of diagram used in computer science and related fields to describe the behavior of systems. State diagrams require that the system described is composed of a finite number of states; sometimes, this is indeed the case, while at other times this is a reasonable abstraction. Many forms of state diagrams exist, which differ slightly and have different semantics.