Making Small Images Into Large Images On The Same Page I am new to the web world need better understanding

HelloI am new at sites and I am trying to make my small images into large images on the same page (Links) however the code that I have been following is not working for me. Is there a way to simplify this more for me?

I only know the html code for this.

 

<img src="imagelink" width="x" height="y">

So, it'll appear something like this... And it seems to not work here, either. But anyway, yeah, this is a code example.

 

<img src="http://forums.xisto.com/no_longer_exists/404.png; width="550" height="316">

 

When the original is like this:

 

 

Just, instead of making it smaller like I did, input bigger values to make it bigger.

Edited October 10, 2010 by Adell (see edit history)