is there a way to use a variable instead of thums1?

document.all.thumbs1.style.visibility = 'visible';

i have a few divs with id's thumbs1, thumbs2, thumbs3...
and i have a next and a back button that goes through the diffrent dives,

function nextBtn(){
 
 document.all.thumbs2.style.visibility = 'visible'; 
  document.all.thumbs1.style.visibility = 'hidden'; 
  }
function prevBtn(){
 document.all.thumbs1.style.visibility = 'visible'; 
  document.all.thumbs2.style.visibility = 'hidden'; 
   }

now it works only if i have two dives. so i want to add a var and use it something like this each time the buttons are pressed stat+=stat();

First, forget about document.all collection! Use document.getElementById() instead of it.
Secondly, show on an example of (x)html-code which will help to understand what is necessary to do.
I believe, that all is very simple, but I not absolutely have understood you.

One way is to recode as;

function nextBtn(ele1,ele2){
 
 document.all.ele2.style.visibility = 'visible'; 
  document.all.ele1.style.visibility = 'hidden'; 
  }
function prevBtn(ele1,ele2){
 document.all.ele1.style.visibility = 'visible'; 
  document.all.ele2.style.visibility = 'hidden'; 
   }

the function call would be

prevBtn('thumbs1','thumbs2')

There are however much simpler ways than having to hard code each element name/id into the function calls.
One would be to have one function that hides all the elements not required then call this before a function showing the one needed.
This is the method I use for http://www.candsdesign.co.uk/article...nus/drop-down/ (JS code available by clicking the Show Code link )