Built-in objects

Earlier in this chapter, you came across the Object() constructor function. It's returned when you create objects with the object literal notation and access their constructor property. Object() is one of the built-in constructors; there are a few others, and in the rest of this chapter you'll see all of them.

The built-in objects can be divided into three groups:

• Data wrapper objects: These are Object, Array, Function, Boolean, Number, and String. These objects correspond to the different data types in JavaScript. There is a data wrapper object for every different value returned by typeof (discussed in Chapter 2, Primitive Data Types, Arrays, Loops, and Conditions), with the exception of undefined and null.

• Utility objects: These are Math, Date, and RegExp, and can come in handy.

• Error objects: These include the generic Error object as well as other more specific objects that can help your program recover its working state when something unexpected happens.

Only a handful...