You may be "shedding" personal details, including e-mail addresses and other contact information, without even knowing it unless you properly configure your Web browser. In your browser's "Setup", "Options" or "Preferences" menus, you may wish to use a pseudonym instead of your real name, and not enter an e-mail address, nor provide other personally identifiable information that you don't wish to share. When visiting a site you trust you can choose to give them your info, in forms on their site; there is no need for your browser to potentially make this information available to all comers. Also be on the lookout for system wide "Internet defaults" programs on your computer (some examples include Window's Internet Control Panel, and MacOS's Configuration Manager, and the third party Mac utility named Internet Config). While they are useful for various things, like keeping multiple Web browser and other Internet tools consistent in how the treat downloaded files and such, they should probably also be anonymised just like your browser itself, if they contain any fields for personal information. Households with children may have an additional security problem - have you set clear rules for your children, so that they know not to reveal personal information unless you OK it on a site-by-site basis?

Cookies are a small amount of information that Web sites store on your computer, temporarily or more-or-less permanently. In many cases cookies are useful and innocuous. They may be passwords and user IDs, so that you do not have to keep retyping them every time you load a new page at the site that issued the cookie. Other cookies however, can be used for "data mining" purposes, to track your motions through a Web site, the time you spend there, what links you click on and other details that the company wants to record, usually for marketing purposes. Most cookies can only be read by the party that created them. However, some companies that manage online banner advertising are, in essence, cookie sharing rings. They can track which pages you load, which ads you click on, etc., and share this information with all of their client Web sites (who may number in the hundreds, even thousands.) It is unknown whether all of these cookie rings (some examples of which are Double Click and Link Exchange) do in fact share user data, but they certainly can do so potentially.

Browsers are starting to allow user control over cookies. Mozilla and Firefox, for example, allows you to see a notice when a site tries to write a cookie file to your hard drive, and gives you some information about it, allowing you to decide whether or not to accept it. (Be on the lookout for cookies the function of which is not apparent, which go to other sites than the one you are trying to load, or which are not temporary). It also allows you to automatically block all cookies that are being sent to third parties (or to block all cookies, entirely, but this will make some sites inoperable). Internet Explorer has a cookie management interface in addition to Netscape like features, allowing you to selectively enable or disable cookies on a site by site basis, even to allow cookies for a site generally, but delete a specific cookie you are suspicious about. With Internet Explorer you can also turn on cookies for a site temporarily then disable them when you no longer need them. For example, at an online bookstore that requires cookies to process an order, but whom you don't want to track what books you are looking at, what links you are following, etc., the rest of the time. Turning on cookie warnings will cause alert boxes to pop up, but after some practice you may learn to hit "Decline" so fast that you hardly notice them any more. The idea is to only enable cookies on sites that require them AND whom you trust.

When mailing to unknown parties; posting to newsgroups, mailing lists, chat rooms and other public spaces on the Net; or publishing a Web page that mentions your e-mail address, it is best to do this from a "side" account some pseudonymous or simply alternate address, and to use your main or preferred address only on small, members only lists and with known, trusted individuals. Addresses that are posted (even as part of message headers) in public spaces can be easily discovered by spammers (online junk mailers) and added to their list of targets. If your public "throw away" address gets spammed enough to become annoying, you can simply kill it off, and start a new one. Your friends, boss, etc., will still know your "real" address. You can use a free (advertising supported) e-mail service provider like Yahoo Mail or Hotmail for such "side" accounts. It is best to use a "real" Internet service provider for your main account, and to examine their privacy policies and terms of service, as some "free mail" services may have poor privacy track records. You may find it works best to use an e-mail package that allows multiple user IDs and addresses (i.e. "personalities", "aliases") so that you do not have to switch between multiple programs to manage and use more than one e-mail address.

The speed of the Internet is often reflected in rapid online acquaintanceships and friendships. But it is important to realise that you don't really know who these people are or what they are like in real life. A thousand miles away, you don't have friends of friends or other references about this person. Be also wary of face-to-face meetings. If you and your new e-friend wish to meet in person, do it in a public place. Bringing a friend along can also be a good idea. One needn't be paranoid, but one should not be an easy mark, either. Some personal information you might wish to withhold until you know someone much better would include your full name, place of employment, phone number, and street address (among more obvious things like credit card numbers, etc.) Needless to say, such information should not be put on personal home pages. (If you have a work home page, it may well have work contact information on it, but you needn't reveal this page to everyone you meet in a chat room.) For this an (sic) other reasons, many people maintain two personal home pages, a work related one, and an "off duty" version.

Realise you may be monitored at work, avoid sending highly personal e-mail to mailing lists, and keep sensitive files on your home computer

In most countries (including South Africa), employees have little if any privacy protection from monitoring by employers. When discussing sensitive matters in e-mail or other online media, be certain who you are talking you. If you replied to a mailing list post, check the headers - is your reply going to the person you think it is, or to the whole list? Also be aware that an increasing number of employers are monitoring and recording employee Web usage, as well as email. This could compromise home banking passwords and other sensitive information. Keep private data and private Net usage private, at home.

There's a high probability that they are gathering this information for direct marketing purposes. In many cases your name and address are worth much more to them (because they can sell it to other marketers, who can do the same again - a snowball effect) than what you are (supposedly) getting from them. Be especially wary of sweepstakes and contests. You probably won't win, but the marketer sure will if you give them your information.

Spam, or unsolicited bulk e-mail, is something you are probably already familiar with (and tired of). If you get a spammed advertisement, certainly don't take the sender up on whatever offer they are making, but also don't bother replying with "REMOVE" in the subject line, or whatever (probably bogus) unsubscribe instructions you've been given). This simply confirms that your address is being read by a real person, and you'll find yourself on dozens more spammer's lists in no time. If you open the message, watch your outgoing mail queue to make sure that a "return receipt" message was not generated, to be sent back to the spammer automatically. (It is best to queue your mail and send manually, rather than send immediately, so that you can see what's about to go out before it's actually sent.) If you have a good Internet service provider, you may be able to forward copies of spam e-mail to the system administrators. They can route a complaint to the ISP of the spammer (or if you know a lot about mail headers and DNS tools, you can probably contact these ISPs yourself to complain about the spammer.)

Never submit a credit card number or other highly sensitive personal information without first making sure your connection is secure (encrypted). In Firefox, look for an closed lock (Windows) or unbroken key (Mac) icon at the bottom of the browser window. In Internet Explorer, look for a closed lock icon at the bottom (Windows) or near the top (Mac) of the browser window. In any browser, look at the URL (Web address) line - a secure connection will begin "https://" instead of "http://". If you are at page (sic) that asks for such information but shows "http://" try adding the "s" yourself and hitting enter to reload the page (for Netscape or Internet Explorer; use whatever method is required by your browser to reload the page at the new URL). If you get an error message that the page or site does not exist, this probably means that the company is so clue less - and careless with your information and your money - that they don't even have Web security. Take your business elsewhere.

On the other side of the coin, your own computer may be a trouble spot for Internet security. If you have an ADSL line or other connection to the Internet that is up and running 24 hours, unlike a modem and phone line connection, be sure to turn your computer off when you are not using it. Most home PCs have pitifully poor security compared to the Unix workstations that power most commercial Web sites. System crackers search for vulnerable, unattended ADSL connected home computers, and can invade them with surprising ease, searching through files looking for credit card numbers or other sensitive data. They can even take over the computer and quietly using it for their own purposes, such as launching attacks on other computers elsewhere - attacks you could initially be blamed for.

When you are considering whether or not to do business with a Web site, there are other factors than a secure connection you have to consider that are equally important to Web security. Does the site provide off-line contact information, including a postal address? Does the site have a prominently posted privacy policy? If so, what does it say? (Just because they call it a "privacy policy" doesn't mean it will protect you - read it for yourself. Many are little more than disclaimers saying that you have no privacy! So read them carefully.) If the policy sounds OK to you, do you have a reason to believe it? Have you ever heard of this company? What is their reputation? And are they backing up their privacy statement with a seal program such as TRUSTe or BBBonline? (Such programs hold Web sites to some baseline standards, and may revoke seal licenses, with much fanfare, of bad acting companies that do not keep their word.) If you see a seal, is it real? Check with the seal-issuing site to make sure that the seal isn't a fake. And examine terms carefully, especially if you are subscribing to a service rather than buying a product. Look out for auto rebilling scams and hidden fees.

Don't give out personally identifiable information too easily. Just as you might think twice about giving some clerk at the mall your home address and phone number, keep in mind that simply because a site asks for or demands personal information from you does not mean you have to give it. You do have to give accurate billing information if you are buying something, of course, but if you are registering with a free site that is a little too nosy for you, there is no law against providing them with pseudonymous information. (However, it would probably be polite to use obviously fake addresses, such as "123 No Such Street, Nowhere, NW 0010, Republic of Nowhereland". If they are generating mailings based on this information presumably in accordance with the terms of their privacy policy - they can probably weed such addresses out and not waste the postage on them.)

Last but certainly not least, there are other privacy threats besides abusive marketers, nosy bosses, spammers and scammers. Some of the threats include industrial espionage, government surveillance, identity theft, disgruntled former associates, and system crackers. Relatively easy to use e-mail and file encryption software is available for free, such as Pretty Good Privacy (PGP), which runs on almost all computers and even integrates seamlessly with most major e-mail software. Good encryption uses very robust secret codes, which are difficult if not impossible to crack, to protect your data. You can also use specialised services (some free, some pay), such as the Anonymizer, which can completely disguise to Web sites where you are coming from and who you are (and block all cookies). Some ISPs are beginning to offer secure, encrypted dial up accounts and other security features. Hopefully some day soon, good encryption and computer security will simply be included in all such services, but for now you have to actively seek out good service