WWW FAQs: Do I need Java and JavaScript?

2006-09-14: The short answer: Java and JavaScript are completely different things. You probably don't need Java. You might need JavaScript, but you already have it. JavaScript improves your experience enough that you should probably leave it turned on.

Java: Ancient History In Web Browsers

Java is something Windows users probably don't already have, and very few users will need. Once upon a time, Java was a popular way to make web browsers more interactive. Today very few websites use Java in that way. Most sites that would have used Java in 1995 use Flash or JavaScript today, depending on what they need to do.

If you do need Java for an unusual site, the site will tell you so. For more information about Java and how to get it if you really need it, see what is Java?

Java is also sometimes used for application programs that run outside of the web browser. The popular Azureus file sharing program is a good example.

Many websites do use Java on the web server, but that does not concern you as a user in any way. What reaches your browser is plain old HTML.

JavaScript: Standard Equipment and Very Useful

JavaScript was included in your web browser. Unless you or your administrator have made a special effort to turn it off, you already have it. JavaScript allows your web browser to deliver more information to you more conveniently without a slow "round trip" to the web server. Many websites use it daily, notably gmail, Yahoo Mail, Yahoo and Google Calendars, Google Maps and anything else with an interface that doesn't make you wait, wait, wait every time you click on anything. These modern interfaces use a set of techniques called AJAX.

I recommend you leave JavaScript turned on, because it makes the web experience so much less painful. However, most websites will still function without it. For more information about JavaScript, see What is JavaScript?

Why Do They Sound The Same?

Java and JavaScript have nothing whatsoever in common. Nothing except a name. They share the word "Java" in their names because of a marketing decision made ten years ago by Sun Microsystems (the inventors of Java) and Netscape (the inventors of JavaScript). And now, well, we're stuck with it!

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