<html>
<body>
<script type=”text/javascript”>
Document.write(“Hello World”)
</script>
</html>
The code above will produce this output on an HTML page:
Hello World!
Example Explained
To insert a
JavaScript into an HTML page, we use the <script> tag (also use the type
attribute to define the scripting language).
So, the
<script type=”text/javascript”> and </script> tells where the JavaScript
stats and ends:
The word document.write is a standard JavaScript command for writing output to a page.
By entering
the document. write command between the <script type”text/javascript”>
and </script> tags, the browser will recognize it as a JavaScript command
and execute the code line. In this case the browser will write Hello World! To
the page:
<html>
<body>
<script type=”text/javascript”>
Document.write(“Hello World”)
</script>
</html>
Note: if we had not entered the <script> tag, the
browser would have treated the document. write(“Hello World”) command as pure
text, and just write the entire line on the page.
Ending Statements With a Semicolon?
With
traditional programming languages, like 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! However, semicolons are required if you want to put
more than one statement on a single line.
How to Handle Older Browsers
Browsers
that do not support JavaScript will display the script as page content. To
prevent them from doing this , we may use the HTML comment tag:
<script type=”text/javascript”>
<!--
Document.write(“Hello World!”)
//- ->
</script>
The two forward slashes at the end of comment line (//) are a JavaScript comment symbol. This prevents the JavaScript compiler from the line.