Show text in the status bar

onMouseOver="self.status='This text goes into the status bar.'; return true;"

This is normally used for links, to give the user more information about the page they are about to visit.
<A HREF="nextpage.html"
onMouseOver="self.status='This page is tremendous, click here'; return true;"
Click here to go to the next page</A>

Example :-
The code for this link go back a page is
<A HREF="javascript:history.back()"
    onMouseOver="self.status='Click here to go back a page'; return true"
    onMouseOut="self.status='';">go back a page</A>

You can also use it to put text permanently in the status bar. This page, when loaded, will display "I am not a number I am a free man!" because the <BODY> tag has this code for the onLoad event. When the mouse moves over the link, it will change. When the mouse moves off the link, the status bar is cleared.