Internet Explorer, Firefox, Opera, and other browsers keep surprisingly accurate records of your online activities, and not just in their history windows. Clearing out the virtual breadcrumbs in your Internet cache and browser histories not only helps preserve your privacy, it also can improve your PC's performance by letting you regain some disk space. Emptying the cache may even help a balky Web site load correctly. The following tips will help you find out what other people can discover about your browsing habits in IE 6 (with Windows XP Service Pack 2), Firefox 1.5, and Opera 8.51.
Manage Your Cookies
How does Amazon.com know that it's you, Joe Schmoe, when you browse for books? Why does the site for the New York Times ask you to log in with a user name and password when you browse from the public library, but log you in automatically when you visit from your home computer? Cookies. Sites embed these small text files containing information about you on your PC when you visit. As a rule, cookies aren't a threat to your privacy. The files usually exchange information only with the sites that placed them. Sensitive cookie content (such as log-in and password information) is often encrypted as well. In other words, Amazon.com won't go telling the New York Times that you've been reading trashy novels.
Nevertheless, the mere presence of cookies called, say, "hooters.com" or "monster.com" (cookies are usually named for the sites they connect to) on your work PC could cause problems. And anyone who has access to your system when you're away can see not only which sites are storing cookies on your PC, but also the contents of unencrypted cookies.
Third-party cookies present a slightly greater privacy threat. These files usually come from banner ad services, which may use them to track your browsing at sites served by the ad network and subsequently present ads that target your interests. Antispyware programs often flag and remove third-party cookies, but you can set your Web browser to bar them from your computer altogether.
Internet Explorer: Choose Tools, Internet Options. Under the General tab, click Settings in the 'Temporary Internet files' area. In the Settings dialog box, choose View Files to open a folder window that displays your browser cookies and cached Web sites. To see just the cookies, click the Name column, and then scroll down to the files starting with 'Cookie:'. To delete a cookie, simply right-click it and choose Delete. When you're done, close the folder window. To remove all your cookies, click Tools, Internet Options, select the General tab, and choose the Delete Cookies button. To block only third-party cookies, choose the Privacy tab and move the slider to the level that suits you. The Medium High setting lets me browse the Web normally without endless IE interruptions that ask if I want to accept a particular site's cookie. Click Sites to add the addresses of the sites whose cookies you want to block (or allow) always. When you finish, click OK twice. Note that the cookies set by sites on your 'Always allow cookies from' list will also get the boot when you delete all in IE, Firefox, and Opera.
Firefox: The Mozilla Foundation's browser comes with a handy self-destruct button labeled Clear Private Data that erases all your personal info at once (see "Cover Your Firefox and Opera Tracks in One Click" later in this article). But the program also gives you finer-grained control over cookie behavior: Choose Tools, Options, select Privacy in the topmost panel, and click Cookies. To block third-party cookies used by ad networks, check the box next to for the originating site only. To specify sites whose cookies you want to allow or block, click Exceptions, enter their URLs in the 'Address of web site' field, and click either Block or Allow. When finished, click Close.
Firefox's convenient cookie view lets you browse, search, and delete individual cookies: Click the View Cookies button under the Privacy tab in the Options dialog box. To search for cookies containing specific text, type the term into the Search field, or browse to and expand individual site addresses to reveal their related cookies (see Figure 1
Opera: This browser makes it easy to remove your Web surfing traces. Like Firefox and IE, however, Opera also allows you to control cookies one at a time: Choose Tools, Preferences, select Advanced, and click Cookies in the left pane. To block third-party cookies, choose Refuse all cookies in the drop-down menu under 'Third party cookies'. Check Delete new cookies when exiting Opera to prevent the browser from saving new cookies that sites create during that session. This transforms all new cookies into session cookies, so it prevents ad networks from tracking your movements online.
To delete cookies individually, click Manage cookies under the Advanced tab in the Preferences dialog box, and either use the search field at the top of the window to find a specific cookie or browse the folders by Web site. As in Firefox, you must click each site's folder icon to display its cookies, which you can edit or delete by clicking the appropriate button.
You can block all cookies for a specific site, too (the default is to accept them): Select the site's folder (rather than the cookies under it), click Edit, and uncheck Use defaults for normal cookies, Accept cookies for server/domain, and/or Accept third party cookies for server/domain (see Figure 2
Downloads Are History
Firefox and Opera keep track of your file downloads as well as your Web browsing history (which IE also logs). Follow these steps to wipe the slate clean.
Internet Explorer: Press <Ctrl>-H to display the browser's History pane, which lists visited sites chronologically and by domain. Right-click a day, week, or domain and choose Delete to remove all of the pages, or choose Expand to display all pages listed for the site. Right-click a page and choose Delete to clear it from IE's history (see Figure 3
Firefox: Press <Ctrl>-H to view the History list. To delete individual history entries, choose a chronological or alphabetical hierarchy in the View menu (the default is chronological, from most recent to oldest). Now browse to the domain, date, or page you want to expunge, right-click it, and choose Delete. Click the red X in the top-left corner to close the History pane.
To wipe out Firefox's entire record of your browsing activity, choose Tools, Options, Privacy, History, Clear Browsing History Now (this dialog box also lets you set the number of days your history is recorded). Click OK when you're finished. To clear the browser's history of your file downloads, press <Ctrl>-J to open the Downloads window and click Clean Up. Firefox clears the download history automatically if you choose Tools, Options, Privacy, Download History and select either Upon successful download or When Firefox exits in the drop-down menu next to 'Remove files from the Download Manager'.
Opera: To view Opera's browsing history, press <Ctrl>-<Alt>-H; or if you have the browser's Panels showing (View, Toolbars, Panels), click the History icon on the left side of the Opera window. To delete a history item, right-click it and choose Delete.
To erase all entries from the History list, choose Tools, Preferences, Advanced, History, and click Clear next to 'Visited addresses'. To wipe out the browser's download history, press <Ctrl>-<Alt>-T, right-click a downloaded file, and click either Remove transfer or Remove all finished (to clear all completed downloads from the list).
Clear the Cache
All browsers save the HTML files and images on the pages you visit, so they can load the pages much faster the next time you visit. This browser cache also lets you view pages--minus some of their dynamic features, such as near-real-time stock quotes--while offline. But the cache serves as a record of your Web travels, too. Follow these steps to examine and empty your browser's cache.
Internet Explorer: Choose Tools, Internet Options, and click the Settings button under the General tab. Select View Files to open a folder window showing what IE stored while you were browsing. Delete individual items there if you want. To wipe the cache entirely, close the folder window, return to IE's Internet Options dialog box, click Delete Files under the General tab, check Delete all offline content, and click OK twice.
Firefox: Unlike IE, Firefox doesn't provide a way to view its cached files, but deleting them is easy: Choose Tools, Options, Privacy, Cache, Clear Cache Now, OK.
Opera: To clear Opera's cached files, choose Tools, Preferences, Advanced, History, select Empty now next to 'Disk cache', and click OK.
Passwords and Form Fillers
Any browser can store and automatically enter personal data required by Web forms. Here's how you can modify, retrieve, or delete that data.
Internet Explorer: IE's AutoComplete feature fills in the blanks for you, and it also logs you in to Web sites automatically, remembering what you type as you type it. To activate AutoComplete, choose Tools, Internet Options, Content, AutoComplete. Check the tasks you want AutoComplete to handle, or click Clear Forms or Clear Passwords to erase previously saved form and log-in information (see Figure 4
Firefox: Choose Tools, Options, Privacy, Saved Forms, Clear Saved Form Data Now to wipe information from Firefox's form filler. To erase saved passwords, click Passwords, View Saved Passwords, Remove All (select Show Passwords and click Yes at the warning if you need to jot any down). Click Close and OK when you're done.
Opera: Site passwords are hidden away with the cookies in this browser. To delete stored passwords, choose Tools, Preferences, Advanced, click Cookies in the left pane, and select Manage cookies. Uncheck Cookies, and then check Wand logins to view only your stored passwords. To delete a password, select the site or log-in item and click Delete. Choose Close and OK to return to Opera.
Browser Tip: Cover Your Firefox and Opera Tracks in One Click
Both Firefox 1.5 and Opera 8.51 offer menu commands and settings that automate the process of removing the personal data they store; version 7 of Internet Explorer will offer a similar feature when it debuts later this year.
Firefox: To delete your personal data in Firefox at once, choose Tools, Clear Private Data, select the types of data you want to remove, and click Clear Private Data Now. By default, Firefox deletes your browsing history, form data (which may include credit card numbers), download history and cache, and authenticated sessions (which may include passwords), sensibly leaving saved passwords and cookies intact. To configure Firefox to clear your personal information automatically, choose Tools, Options, Privacy, Settings, check Clear private data when closing Firefox, and click OK twice.
Opera: When it comes to privacy, the browser from the balmy shores of Norway doesn't mess around. To wipe out your browsing traces, choose Tools, Delete private data, and click Delete to clean out everything except your saved passwords. To choose which items to clear, click Advanced; check or uncheck the available history, cache, cookie, and other options; and then click Delete.