Mozilla has been feasting on the cookies, and now it wants to share them. The non-profit organization behind the popular Firefox web browser has announced the release of a new add-on called Lightbeam, that lets users track the cookies that track them across the web. With the add-on, users will be able to identify each cookie that’s placed on their machine, see what companies put them there, and what kind of information they’re gathering.

If you don’t know what a ‘cookie’ is, essentially its a file stored on your web browser that’s used to track your browsing history as you traverse the web. The main culprits for placing cookies on your browser are ad networks run by the likes of Google, who are able to identify site visitors based on those cookies, and note how often users visit certain sites, as well as those sites’ content. Using this information, Google then tries to serve up targeted ads, based on what it thinks you might be interested in.

Lightbeam, introduced on the Mozilla Blog by its privacy expert Alex Fowler, aims to show users exactly who is behind each cookie placed on your machine, and it’s often quite eye-opening. For example, an ad network might place a cookie, but the data it gathers might be shared with dozens of different companies. In a video posted on the Mozilla blog, Fowler reveals that by visiting just four websites in the morning, he’s interacting with more than 120 different companies.

Lightbeam can be accessed within the Firefox browser, and basically creates a ‘snapshot’ that lets you visualize the companies behind each cookie either as a kind of tag cloud or a meter. Mozilla says that the aim of Lightbeam is to help its users better understand the relationship between first and third-party websites. In addition, it’s also asking users to help contribute data to Lightbeam’s database.

“Call it a Wizard of Oz moment for the web, where users collectively provide a way to pull back the curtain see its inner-workings,” writes Fowler.

How Does The Cookie Crumble?

The use of cookies to track web users has been hotly debated for years. Despised by privacy advocates like the Electronic Frontier Foundation, they allow advertising networks to build up a wealth of information about you, such as your name, email, phone number, location, age, demographic, marital status, health conditions, likes, dislikes, habits and more. This data is then sold to all kinds of third-parties, including insurance companies and credit agencies as well as other advertisers. In addition, this data can also be passed on to government agencies if they so request it.

Not surprisingly, many people choose to circumvent cookies, either by deleting them, or browsing the web anonymously. Lightbeam gives users the choice of blocking certain cookies, and alternative add-ons like Do Not Track Me and Ghostery do an even better job of it. Then there’s the Tor browser, which allows you to browse the web anonymously and side-step those cookies, whilst its also possible to visit some tracking companies web pages and opt out.

Of course, we should point out that not all cookies are bad. These files are often used to help you save time by storing your site preferences and automatically filling out web forms. They’re used to keep you logged in on social networks like Facebook, and to store items in your shopping basket on sites like Amazon. Webmasters also use them just to keep count of their site visitors.

But whether you choose to delete or block cookies or not, there are few downsides to making third-party tracking requests more transparent. If nothing else, Lightbeam reveals just how pervasive tracking has become across the web – there’s hardly a site in sight that doesn’t track you somehow. Only when people start realizing that visiting a certain website gives their presence away, and not just to one company but to maybe ten or twenty third-parties as well, will they become more informed. And only when people are better informed, can they decide if they really want to be tracked or not.