<html>
<body>
<script type="text/javascript">
var d = new Date()
var time = d.getHours()
if (time<10){
document.write("<b>Good morning</b>")
}elseif (time>10 & time<16){
document.write("<b>Good day</b>")
}else{
document.write("<b>Hello World!</b>")
}
</script>
</body>
</html>