There are many people out there complaining about the Firefox RAM Memory Bug. Lets get it straight. It's not a bug. It's part of the cache feature. This 'feature' is how the pages are cached in a tabbed environment. To improve performance when navigating (studies show that 39% of all page navigations are renavigations to pages visited less than 10 pages ago, usually using the back button), Firefox implements a Back-Forward cache that retains the rendered document for the last five session history entries for each tab. This is a lot of data. If you have a lot of tabs, Firefox's RAM memory usage can climb dramatically. It's a trade-off. What you get out of it is faster performance as you navigate the web.
Now a lot of people have found the 'secrets' on how to manipulate settings in "about:config" to drop the memory usage as long as possible and to increase the speed at which Firefox loads sites. Read on to find out how to do this.