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JavaScript: Object Oriented ProgrammingAn object is basically a black box which stores some information. It may have a way for you to read that information and a way for you to write to, or change, that information. It may also have other less obvious ways of interacting with the information The directly accessible bits of information in the object are its properties. The difference between data accessed via properties and data accessed via methods is that with properties, you see exactly what you\\\\\\\\'re doing to the object; with methods, unless you created the object yourself, you just see the effects of what you\\\\\\\\'re doing. Your web page document is an object. Any table, form, button, image, or link on your page is also an object. Each object has certain properties (information about the object). For example, the background color of your document is written document.bgcolor. You would change the color of your page to red by writing the line: document.bgcolor="red" The contents (or value) of a textbox named "password" in a form named "entryform" is document.entryform.password.value. Some of the information in the object may actually be directly accessible; other information may require you to use a method to access it - perhaps because the way the information is stored internally is of no use to you and the object needs to check that you don\\\\\\\\'t access them (knowingly or unknowingly) Most objects have a certain collection of things that they can do. Different objects can do different things, just as a door can open and close, while a light can turn on and off. A new document is opened with the method document.open() You can write "Hello World" into a document by typing document.write("Hello World") . open() and write() are both methods of the object: document. ¤ Events
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