This is an introductory course in multivariable calculus. So far, your study of calculus has concentrated on the study of one function of one variable y=f(x), which can be graphed in the plane. In this course, you will study functions with two or three dependent variables, such as (x,y,z)=(x(t),y(t),z(t)) (which describes a curve in space), or two or three independent variables, such as z=f(x,y) (which describes a surface in space). Such functions are much more common in real-world applications of calculus that functions of one variable; they are needed to represent, for example, the path of a baseball as a function of time, or the altitude at a point in Seattle as a function of its map coordinates. You will learn how to interpret such functions geometrically, using vectors; and you will learn how to use calculus to solve such problems as finding the maximum and minimum values of temperature in a sheet of metal, or determining in what direction the altitude is increasing or decreasing fastest at a given point in Seattle. Because most of the action is taking place in 3-dimensional space, you will have to learn new ways to think geometrically and to interpret graphs.