Have you ever wondered whether surfing really is anonymous?

You browse the internet, you open and close websites, and you do not enter personal information, at least not often. While you do that, each and every page you visit leaves a little trace behind. If this information is not deleted, it can be used not only to track your browsing habits, but also to find out who you are.

Are you curious to find out [NO LONGER WORKS] What The Internet Knows About You? Then visit that link and see whether the information displayed is vaguely familiar. My result revealed that I had visited 65 of the 5,000 most popular internet websites.

what the internet knows about you

And there is more. Did You Watch Porn? If your significant other checks your browser(s), he'd better find this:

what the internet knows about you

Not shocked, yet? Maybe you are using XING. If you are, you will be interested in This Experiment.

what the internet knows about you

It demonstrates how your anonymity can be lifted based on the social network groups you belong to. And this doesn't work for just XING! If you are an active user of any social network, you likely belong to different groups within the network. Your group profile is almost like a fingerprint. The more groups you belong to, the less likely there will be someone else who is assigned to exactly the same groups and no others. The group traces left in your browser can lead back to who you are - your profile and eventually your real name.

So how can any website out there get access to this type of information?

History

Your browser stores a history of websites you have visited. Firefox typically records the past 7 days of browsing, downloads, as well as search and form history. Anyone who can open your browser has access to this information. Moreover, any website you open can look into your browser history and see which other websites you have been visiting. This information is being used to display custom information to you.

If you are uncomfortable with this type of information being available, you can customize your browser settings and disable history. In Firefox, go to > Tools > Options and navigate to the > Privacy tab.

what the internet knows about me

Here you can choose the settings you're comfortable with, for example > Clear history when Firefox closes or use the private browsing session.

Cookies

The screenshot above also shows what other traces websites leave on your computer: cookies.

Cookies are used to store user preferences, for example options, the contents of your shopping cart, or even usernames and passwords. Cookies are only text files, which can easily be viewed and will reveal which sites they originate from. So they are yet another threat to your privacy.

In Firefox, you can disable or remove cookies through the > Tools > Options > Privacy tab. Make your selection which types of cookies you would like to accept. To view or remove existing cookies, click on > Show Cookies and the menu shown in the screenshot below will open. You can remove individual cookies or all cookies at once.

what the internet knows about me

This is probably the least known "open door" to your privacy. All browsers can mark links to websites you have previously visited in a different color. For example, when you search Google, you immediately recognize which website you have already visited based on the link color.

what the internet knows about me

While disabling browser history can be quite uncomfortable, disabling CSS styling information comes at a lower cost, but is just as effective. How it works is that your browser will not return information to a website, revealing whether or not you have already visited that or other websites. Hence, that website won't be able to color code visited links or sniff out information about you.

In Firefox 3.5 you can easily disable visited links. Type > about:config in the address bard of your browser, filter for > layout.css.visited_links_enabled and double click the item to set its value to > false.

For Firefox, there are also several extensions and options that will protect your privacy. Here are a few articles you may want to review:

Guy showed you how to Really Delete Your Browsing History.

Varun compiled the 10+ Best Firefox Security and Privacy Addons.

Whether you disabled and cleared your browser history or disabled CSS visited link styling information, the result of [NO LONGER WORKS] What The Internet Knows About You should now be negative, the XING experiment should not reveal your name, and your significant other will never find out whether or not you did watch porn. Hooray for privacy!

safe browser history

Did the internet know anything about you that got you worried?

Image credits: mzacha