Vector analysis is the calculus of functions with variables as vectors—a part of calculus also known for its derivative and integral equations. The components of a vector do not always have to be constants. They can also be variables and functions of variables, such as the position of a body moving through space represented by a vector whose *x, y*, and *z* components are all functions of time. In this case, the calculus can be used to solve such vector functions, which are also called vector analysis.