JavaScript How To ...

Use the <script> tag to insert a JavaScript in an HTML document.

Examples

Write text
How to write text on a page

Write text with formatting
How to format the text on your page with HTML tags

How to Put a JavaScript Into an HTML Document

<html>
<head>
</head>
<body>
<script type="text/javascript">
document.write("Hello World!")
</script>
</body>
</html>

And it produces this output:

Hello World!

To insert a script in an HTML document, use the <script> tag. Use the type attribute to define the scripting language.

<script type="text/javascript">

Then comes the JavaScript: In JavaScript the command for writing some text on a page is document.write:

document.write("Hello World!")

The script ends:

</script>

Ending Statements with a Semicolon?

With the traditional programming languages C++ and Java, each code statement has to end with a semicolon.

Many programmers continue this habit when writing JavaScript, but in general, semicolons are optional and are required only if you want to put more than one statement on a single line.

How to Handle Older Browsers

Older browsers that do not support scripts will display the script as page content. To prevent them from doing this, you can use the HTML comment tag:

<script type="text/javascript">
<!--
    some statements
//-->
</script>

The two forward slashes in front of the end of comment line (//) are a JavaScript comment symbol, and prevent the JavaScript from trying to compile the line.

Note that you can't put // in front of the first comment line (like //<!--), because older browsers will display it. Funny? Yes! But that's the way it is.

Computer Joke

My Grandmother: "I can't find my sloppy disk!"

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