Show a messagebox By javascript

If you want to give a message to User thesn Simply right a javascript.Basically most of the websites uses this messagebox to show any kind of error or message to the User

To Show this Message simply write a script in header Section of your Html
I have Used this message to show when somebody clicks on a buton

This is the code you need to write in header section of your html

<script type="text\javascript">
function message(){
     alert("Type your message here");

Write this code into your body part

<input type="button" onclick="message();" value="click me" />