The Javascript tutorials are intended for complete beginners to the subject. If you've never done any programming before in your life, then this is the place to be. Complete the entire course and you'll have a very good understanding of prgramming in general, and Javascript in particular.
We're going to study the JavaScript programming language, because it is a widely-used scripting language for web pages. All the scripts in these pages have been tested with modern versions of a wide variety of browsers. If you're ready, then, let's make a start.
A First Script
Let's jump right in with a bit of code. Fire up whatever HTML Editor you use (you can use our free Editor by clicking here: Download the free editor ). With your editor open, copy the following code. When you're done copying it, save your work and load it into your browser.
<HTML>
<HEAD>
<TITLE>A First Script</TITLE>
</HEAD>
<BODY>
<SCRIPT LANGUAGE = JavaScript>
document.write("Hello World")
</SCRIPT>
</BODY>
</HTML>
All right, how did you get on? All that typing should have gotten you this in the browser:
"Hello World"
Granted, that's a heck of a lot of trouble to go to just to write "Hello World". But it's a start. Let's explain what's going on.
When you're writing your scripts, you enclose them between two <SCRIPT> tags, an opening one and a closing one. The opening one should tell the browser what language the script is written in:
<SCRIPT LANGUAGE = JavaScript>
The closing Script tag is just the word SCRIPT in between two angle brackets with a forward slash:
</SCRIPT>
Most of your JavaScript will go between these two tags. So what's all that "document dot write" bit?
document.write("Hello World")
Document is part of something called the Document Object Model. Document refers to all the text and HTML elements between the two BODY tags. And that includes any attributes inside the BODY tag itself. Like BGCOLOR.
Write( ) is a method of Document. A method is a bit of code that actually does something. As opposed to a Property, which IS something. Methods are usually Verbs, and Properties usually Nouns. The Write( ) method writes text (and numbers as well) between the two BODY tags on your page.
For all you English language experts out there who might be protesting about the lack of capital letters, Document is spelt with a lowercase "d", and Write with a lowercase "w". Try changing your code to this and see what happens:
Document.Write("Hello World")
JavaScript is damned picky about capital letters - it doesn't like them at all!
The part or parts between the two brackets of write( ) are what will be written to your page. Direct text goes between two double quotes; Variables don't need any. Whoops, we haven't done variables yet. We'll get to them.
So the whole line reads "Write the text Hello World between the two BODY tags of the web page."
Don't worry if you don't understand some of that - the main point is that you are up and running, and you've written your first script. The journey has just started.
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