HTML jump menu and PHP problem

[shibbi3]

Hello Everyone,

I am pretty new at PHP and I dont know if it is required for what I want to accomplish, but here is my problem:

I created a jump menu in HTML

<select name="menu1" onChange="MM_jumpMenu('parent',this,0)">
<option selected>unnamed1 </option>
<option>unnamed2</option>
<option>unnamed3</option>
</select>

and what I want to accomplish is if i selected option 1 I want to echo something on the exact same page say index.php without going to a different page, and same goes for option 2 and 3. I've seen this done on some pages and I just want to know how they achieve it without making a totally new page for each option and updating the current page as you move through the selection. It seems kinda neat, any help would be awesome! thanks.

shib