Privacy is very important to me so I assume it is very important to you as well. To that end I protect my online privacy by being aware of what information Websites collect and require from their visitors. For example, you’re only here to read some articles. So I don’t need you to create an account and won’t ask you to do that. You can keep your email address, credit card information, and other personal information.
But the Web server collects some data about your visit, including the IP address you’re connected to the Internet through and what browser you use. This information may be given to authorities without my knowledge or permission (that’s the law!).
Most Websites now use cookies. For example, this site is published through WordPress, which uses cookies for benign reasons. Your browser may set a cookie to remind itself later of which pages on this site you have already looked at or which links you have clicked on.
If you see advertising on this Website it was probably served by a third-party service like Google AdSense. Those advertising services may set cookies in your browser to help them track you across Websites or to record which ads you have seen (and clicked on). You can clear those cookies from your browser or you can install a plugin to help you manage your cookies.
If it seems to you like certain ads are following you around, they may be. There is something called “interest-based advertising” where the networks pick ads based on the Websites you have previously visited. Advertisers can pay to “tag along” with you. You can opt out of Google’s Interest-based Advertising here (you will still see Google ads but they will be more random). You should also check out the Do Not Track Us Website. But remember that many Websites are now supported by advertising. If the ads are not annoying and popping up in your way then you probably don’t need to worry about them.