Please help me understand this mousover code

[buzzbee]

I have a website, but am looking to change the look of it. I am looking at a free template I like, but there is a piece of code I don't understand. I can see what it does, but not how it does it. I wonder if someone could try to help me make sense of it, so that I can use it properly in the future.
An example of the piece of code is...
"a HREF="products.htm" onmouseover="tabOn("3")" onmouseout="tabOff("3")"
This anchor is round a GIF and whenever the mouse is over the GIF, it highlights the GIF. The page has a CCS style sheet which includes an atribute for A Hover. I presume that this is in some way linked, but am not sure.
The main thing that confuses me is the tabOn("3&quot') and subsequent tabOff.
Whether it makes a difference or not, I don't know, but the next GIF uses "4&quot and the next uses "5&quot etc, but I suspect this probably makes no difference.
The company who provide the template use this same command on the menu of the main page of their own sie at http://www.easyimaging.net/ so this might give you a better idea of what I mean

Any help would be much appreciated
thanks[CODE]

[QuietDean]

tabOn and tabOff will be JavaScript functions.

Have a look in the page (or in an include file, like javascript.js ) looking for

function tabOn(variableName) {
code code...
}

It will all be in there.

[buzzbee]

Spot on - It's in the head.
Downside is that Javascript is all foreign to me. ((

Thanks for your help - Certainly appreciated.

[QuietDean]

no prob. If you want a javascript primer this is pretty good -

http://www.w3schools.org/js

[buzzbee]

Thanks Dean
I'll have a little read through. I've seen a couple of JS tutorials and got a general gist of it, but never really understood it.
Looking through the function involved in the page I am using, it looks pretty basic. I've worked out what it is doing, though am not totally confident with the syntax of it, but I think I will be able to work with it, which is the main thing.

Once again, thanks for your help, and I will take your advice and have a look through that tutorial