The items of data stored in an object are called the properties of the object. As an example, you could use objects to store information about people as in an address book. The properties of each person object might include a name, address, and telephone number.
he document.write function we discussed earlier this hour is actually a method of the document object. You will learn more about this object in Hour 9, "Working with the Document Object Model."
Browser objects are objects that represent various components of the browser and the current HTML document. For example, the alert() function you used earlier in this chapter is actually a method of the window object. You'll explore these in more detail in Hour 9, "Working with the Document Object Model."
Custom objects are objects you create yourself. For example, you could create a person object, as in the examples in this section. You'll learn to use custom objects in Hour 15, "Creating Custom Objects."