meta tag

Giganews Newsgroups
Subject: meta tag
Posted by:  bcampbe… (ABC)
Date: Mon, 07 Jul 2003

Can someone tell me where I can get more info on these 2 meta tags

      <META HTTP-EQUIV="Pragma" CONTENT="no-cache">
      <META HTTP-EQUIV="cache-control" CONTENT="no-cache">

I am using them in my page but it still appears to be caching image
files and Javascript.  Are these tags browser dependent.