How to Clear Private Data From Your Web Browser

For browsing speed and convenience, your web browser keeps a lot of information about what you've been doing online, but there's a lot of reasons why you might prefer that it not. Maybe you're shopping for a secret gift for a significant other who uses the same computer, maybe you're using a public terminal, or maybe you like your privacy. This article is your guide to what your browser tracks and how to make it "forget" at the end of your session.

What your web browser tracks

Cache

As you surf the web, every page you read, image you see, script that's loaded, and so on, must be downloaded from far-away web servers. Your web browser's cache speeds up your browser by storing some of those things in memory and the hard drive so that the next time you visit the page it won't have to download them all over again. Some things are stored in the cache only for a short while, but others can be stored for weeks or even months depending on your web browser.

Cookies

A funny one as technical terms go, cookies are small chunks of information that web sites can store on your hard drive and subsequently access. This enables sites to "remember" things about you and your previous visits. When you "log in" to, say, Hotmail or Facebook, a cookie is created on your hard that, when you come back later, tells the site that you were there before. Advertisers who display ads on multiple sites can also use cookies to identify you as the same person (or web browser) if you visit more than one of those sites.

Browsing, Form, and Search History

For your convenience your web browser saves a "history" of the pages you've visited in the past week, month, or even longer. This lets you quickly jump to a page you've visited previously without retracing your steps. You can access your History in Firefox under the History menu; in Internet Explorer 7 you can find it by clicking on the small downward arrow next to the "Forward" button. Your web browser also saves values you've entered into web forms and the search box.

Taking control of what your browser tracks

Mozilla Firefox

Click on the Tools menu and choose Options... and then click on the Privacy tab. Here you can see all of the sorts of information that Firefox collects and opt in or out of it. You can choose whatever settings you prefer, but I recommend allowing cookies as they're necessary for a lot of functionality on the web these days. If you want some or all of your data to be removed at the end of every session, refer to the options at the bottom under "Private Data." You can choose whether your information should be deleted automatically or if you'd prefer Firefox to ask first, and the Settings... button here lets you choose what will and won't be deleted by default.

Deleting personal data in Mozilla Firefox

Under the Tools menu click on Clear Private Data..., or you can press Ctrl-Shift-Del. The dialog that appears will let you choose which items you want to delete. Check the items you want to delete and click on Clear Private Data Now and it will be done.

Internet Explorer 7

In Internet Explorer 7, click on the Tools menu and choose Internet Options. There, like in Firefox, you'll find a Privacy tab, which is where you'll find the cookie settings. Move the slider up and down to change how different sorts of cookies will be handled--each level is explained in detail to the right of the slider. If you wish to get technical you can click on Sites to black- or whitelist cookies from specific sites, or Advanced to choose your own settings instead of using the slider.

To control how IE7 treats your history and cache (which it calls "Temporary Internet Files"), go to the General tab, where you can click on Settings under Browsing History. Here you can change when and for how long IE will save things in your cache, and below you can change the number of days things will be stored in your cache.

Finally, there's the information that you've entered into form fields, the settings for which can be found on the Contant tab. Click on the Settings button under AutoComplete. There you can control what data is stored.

Deleting personal data in Internet Explorer 7

To wipe your personal data from IE7, click on the Tools menu and choose Delete Browsing History... Here you're presented with buttons to delete your Temporary Internet Files (cache), cookies, history, saved form input, and stored passwords, or all at once. Take care when doing this--once it's done it can't be undone. If you click on the Delete All... button you'll also be given the option to delete information stored by add-ons, so if you've installed a toolbar, for example, and think it might have saved personal information you can use this option. Unfortunately Internet Explorer doesn't give you the option to automatically prompt you to delete information at the end of each session, so you'll have to remember to do it on your own.