Constructors allow you to create an object and provide it with an initial set of data so it can initialize properly. Without constructors, you create an object, then need to all a separate method to initialize it. Two steps.

An object oriented programming concept, used to build an object.

are functions that you use to define the properties and methods of a class. For example, the following code creates a new Circle class by creating a constructor function called Circle: function Circle(x, y, radius){ this.x = x; this.y = y; this.radius = radius;