As we already know, HTML (Hypertext Markup Language) is the language we use to create Web documents. Now we will read "Hello World!"

As given below:

<HTML>

<HEAD><TITLE>My First Page</TITLE></HEAD>

<BODY>

Hello World!

</BODY>

</HTML>

To add JavaScript to a page, you'll use a similar tag: <SCRIPT>.This <SCRIPT> tag tells the browser to start treating text as a script, and </SCRIPT> tag returns to regularly scheduled HTML as given below. Note that file will be stored as .html or .htm.

Output of the above program would be

In this illustration, we placed the script within the body of HTML document. There are essentially four different places where you can use scripts:

• In the body of page. In this case, output of the script is displayed, as part of HTML document, when the browser loads the page.
• In the header of page, between the <HEAD>tags. Scripts in the header aren't executed immediately, however can be referred to by other scripts. Header is generally used for functions.
• Within an HTML tag. This is termed as an event handler and allows the script to work with HTML elements. Event handlers are one kind of script where you do not need to use <SCRIPT> tag.
• In a separate file entirely JavaScript supports use of files with.js extension containing scripts; these can be included by specifying a file in <SCRIPT> tag. This feature works only in Netscape Navigator 3.0 or later and Internet Explorer 4.0 or later.