prompt("Enter Your Name","Enter Here")

<script language="javascript">
var a;
a=prompt("Enter Your Name","Write Here");
document.write("Welcome <b>" +a);
</script>

eval(prompt("",""));

<script>
var age,year,month,week,days,hour,minute,second;
age=eval(prompt("Enter Your Birth of Year",""));
year=2010-age;
month=year*12;
week=year*52
days=year*365;
hour=year*365*24;
minute=year*365*24*60;
second=year*365*24*60*60;
document.write("Your age is <b>" + year +"</b> Years<br>");
document.write("You have seen <b>" + month +"</b> Month<br>");
document.write("Your have seen <b>" + week +"</b>Weeks<br>");
document.write("Your have seen <b>" + days +"</b>Days<br>");
document.write("Your have seen <b>" + hour +"</b>hours<br>");
document.write("Your have seen <b>" + minute +"</b>Minutes<br>");
document.write("Your have seen <b>" + second +"</b>Seconds<br>");

document.write("<br><hr>");
document.write("<center>Made By Waqas Ali Qureshi</center>");
</script>