Javascript function to disable right click

Disabling right click using Javascript function.

<script language="javascript" type="text/javascript">var IE;var NN;if(navigator.appName=="Microsoft Internet Explorer"){     IE=true;}if(navigator.appName=="Netscape"){    NN=true;}function right(click){    if(IE&&(event.button==2||event.button==3))    {        alert('The right click is disabled');        false;    }        if(NN&&(click.which==2||click.which==3))    {       alert('The right click is disabled');       false;    }}if(document.layers)window.captureEvents(Events.MOUSEDOWN)if(document.layers)window.captureEvents(Events.MOUSEUP)document.onmousedown=right;document.onmouseup=right;window.document.layers=right;</script>