Surfing the web may be liked to navigating a busy street. If you are absentminded, you might find your handbag snatched or get pushed into a puddle; you might end up on the receiving end of a dubious deal from a roadside vendor; or worst of all, you might be run over.

Similarly, getting careless on the web could find you becoming the victim of a phishing attack or scam — the worst-case-scenario here is identity theft. Thus, being armed with the right kind of information is critical to online safety. This includes not just knowing what can go wrong, where and how, but also being aware of what your browser reveals about you to the sites you visit.

We all know that websites collect information about us—sometimes that is necessary, such as for mail, banking, social networking, etc. At other times it is to identify where we come from in order to target content (for instance, news and advertising) and services, and even (controversially) censorship; track what links we go to and which advertisements we click on, what ISP, browser, operating system we are on, what our screen resolution is, and so on. They can do this in a number of ways—including setting cookies and logging our IP addresses.

But did you know that some sites are also able to approximate our physical location and target content based on that information? This takes place by a method called geolocation, the term being self-explanatory. Most modern-day browsers are geolocation-enabled by default.

While visiting websites that make use of geolocation information, users on a geolocation-enabled browser are asked to share their location. If they agree, their computer’s IP address, information about wireless access points in the vicinity, and a random client identifier (that expires every two weeks) are sent to Google’s location services. This in turn attempts to approximate the user’s geographical location and sends the information back to the browser which then passes it on to the website.

However useful geolocation-enabled browsing might be—such as getting information about the local area, and pinpoint landmarks and services there—users have a right to decide whether they want to share this information. Fortunately, geolocation can be easily turned off (or back on). Here’s how:

n In Firefox, type about:config in the address bar and then click past the warning (while taking heed of it) not to mess with advanced settings. Search for ‘geo.enabled’ in the filter box, and set the value to false.

n In Chrome, go to Options → ‘Under the Hood’. Click on ‘Content Settings’ and then select the Location tab. Make your selection based on whether you want to turn geolocation off completely or you want to make a decision on a site-by-site basis.

n In Opera, type ‘about:config’ in the address bar to enter the advanced browser preferences area. Start typing ‘geolocation’ in the ‘Quick find’ box for the Geolocation panel to be displayed. Uncheck the ‘Enable geolocation’ box.

n In Internet Explorer, geolocation is available through the Google Toolbar. This is turned off by default, but in case you do turn it on and change your mind later, it can be toggled from the Tools section of IE settings (the wrench icon).

n In Safari, go to Preferences → Security. Uncheck the ‘Allow websites to ask for location information’ option under ‘Location services’.

Payal Dhar is a freelance technology writer