Most people surf the web and chat online thinking that they are hidden behind the anonymity of the computer screen. Few people realize that they are leaving footprints all over the web anytime they go online. Here are some of the things that are automatically sent to the website's computer whenever you visit the site:
- Your IP address - Every computer on the internet is assigned a specific, unique IP (internet protocol) address. That IP address can't be easily traced to a name directly except by your internet service provider but it can be correlated with your other online activity. So if you disclose your name in a blog or when writing a book review, someone might be able to trace that back and match it to your other internet habits. You can look up your current IP address at showmyip.com.
- Your computer's software load - Many websites want to know what web browser you are using (including which version). Legitimate sites use this information to adjust for differences between the way browsers display the webpage. A page that looks fine on Internet Explorer may not display properly through Mozilla's Firefox so the website developer adds code to tweak the display based on your browser. Unfortunately, the information sent to the website does not end with the browser. They may also be able to read your operating system and other details.
- Your page visit history - The website can often track which pages you visited, how long you stayed on a given page and where you were just before you came to the website. (This is often helpful for companies who want to know if you came to the site from a search engine and if their advertising dollars are being well-spent.)
On the other hand, If the site you're visiting is malicious, all bets are off. Your privacy is completely dependent on the strength of your antivirus/antispyware programs and how up-to-date you keep your patches. Hackers at these sorts of sites can use all sorts of techniques to either steal information or trick you into revealing more than you intended. They will try to steal passwords (knowing that many people reuse the same password and that, by compromising this password, they have a very good guess at your online bank or work password), load viruses and may even attempt to alter the security settings on your computer so that they can access and use your computer for other malicious activity.
You can reduce the amount of information revealed about yourself by only visiting legitimate sites, checking privacy policies and paying careful attention to the personal information you provide. Don't post your address, password, or credit card information unless you trust the site. Look for indications that the site uses SSL to encrypt your information. Limit what cookies you allow and be careful which web sites you visit; if it seems suspicious, leave the site.