JavaScript Tutorial/Document/title
Assign value to the document title (you must have the title tag in your html document)
<source lang="javascript">
<html> <head> <title>Untitled</title> <script language="javascript" type="text/javascript"> function changeTitle() {
var newTitle = prompt("A title.", "default title"); window.document.title = newTitle;
} </script> </head> <body>
You can change <a href="javascript:changeTitle()"> the <title> element</a> on this page
</body> </html></source>
document.title
The title property is a read-only string that specifies the title of the document.
This property is commonly set with the tag.
<source lang="javascript">
<html>
<head><title>My Web Page</title></head> <script> </script> </html></source>