An anonymizer is a service for web users who wish to keep their browsing activity private. Rather than accessing web pages through their browsers directly, people using an anonymizer request pages through the service. The service accesses the page and relays it to the browser. Thus, statistics about the user, such as the person's Internet protocol (IP) address, browser version, and so forth, are not collected. This allows people to access pages with a degree of anonymity.
The most basic kind of anonymizer is a single point system. Requests for web pages go from the user to the anonymizer to the end page, and then back again. In a networked system, requests are sent through multiple layers of anonymizers, designed to obscure details as much as possible. This also reduces security risks, because if one anonymizer is compromised, the user's identity will still not be revealed.
There are a number of ways people can use such systems, ranging from using a web page to installing a browser plug in. Such services are intended to reduce risks, but they can also carry risks of their own. It is important to use a trusted anonymizer, as otherwise the system can inject malicious code or other materials as people access web pages. This can create security risks for users as well as the sites they interact with; someone sending email through such a service, for example, might end up sending viruses along with the contents of the emails.
The security of the service is also not necessarily guaranteed. If the servers are hosted in a country where companies can be compelled to turn over records by law and records of users are kept, these can end up in the hands of law enforcement. People using the Internet for malicious activity may be tracked down this way, along with people like political dissidents, who may use anonymizers for safety. While statements may be made about security and privacy, it is difficult to verify these statements and there is a certain amount of risk involved in using such services.
Asking other computer users for recommendations can help people find a reasonably secure and reliable anonymizing service. Experienced coders can also create their own and use it within a networked system or as a single point system, depending on their inclinations. People should be aware that some anonymizers specifically do not offer protections to people involved in illegal activity, and will turn records on such activities over to law enforcement.