Web tracking is the practice by which operators of websites and third parties collect, store and share information about visitors' activities on the World Wide Web. Analysis of a user's behaviour may be used to provide content that enables the operator to infer their preferences and may be of interest to various parties, such as advertisers. Web tracking can be part of visitor management.

Uses

The uses of web tracking include the following:

Methods

IP address

Every device connected to the Internet is assigned a unique IP address, which is needed to enable devices to communicate with each other. With appropriate software on the host website, the IP address of visitors to the site can be logged and can also be used to determine the visitor's geographical location. Logging the IP address can, for example, monitor if a person voted more than once, as well as their viewing pattern. Knowing the visitor's location indicates, besides other things, the country. This may, for example, result in prices being quoted in the local currency, the price or the range of goods that are available, special conditions applying and in some cases requests from or responses to a certain country being blocked entirely. Internet users may circumvent censorship and geo-blocking and protect personal identity and location to stay anonymous on the internet using a VPN connection.

HTTP cookie

A HTTP cookie is code and information embedded onto a user's device by a website when the user visits the website. The website might then retrieve the information on the cookie on subsequent visits to the website by the user. Cookies can be used to customise the user's browsing experience and to deliver targeted ads. Some browsing activities that cookies can store are:

First- and third-party cookies

A first-party cookie is created by the website the user is visiting. These cookies are considered "good" since they help the user rather than spy on them. The main goal of first-party cookies is to recognize the user and their preferences so that their desired settings can be applied. A third-party cookie is created by websites other than the one a user visits. They insert additional tracking code that can record a user's online activity. On-site analytics refers to data collection on the current site. It is used to measure many aspects of user interactions, including the number of times a user visits. Restrictions**** on**** third-party cookies introduced**** by**** web browsers**** are bypassed**** by**** some**** tracking**** companies using a technique called**** , where a third-party tracking**** service is**** assigned**** a DNS record**** in**** the first-party origin**** domain**** (usually**** CNAME)**** so**** that**** it****'s masqueraded as**** first-party even**** though**** it****'s a separate**** entity**** in**** legal and organizational**** terms.**** This technique is blocked by some browsers and ad blockers using block lists of known trackers.

ETags

Other methods

Unethical Nature of Web Tracking

Web browsing is linked to a user's personal information. Location, interests, purchases, and more can be revealed just by what page a user visits. This allows them to draw conclusions about a user, and analyze patterns of activity. Use of web tracking is unethical when applied in the context of a private individual; and to varying degrees is subject to legislation such as the EU's eCommerce Directive and the UK's Data Protection Act. When it is done without the knowledge of a user, it is considered a breach of browser security.

Justification

In a business-to-business context, understanding a visitor's behavior in order to identify buying intentions is seen by many commercial organizations as an effective way to target marketing activities. Visiting companies can be approached, both online and offline, with marketing and sales propositions which are relevant to their current requirements. From the point of view of a sales organization, engaging with a potential customer when they are actively looking to buy can produce savings in otherwise wasted marketing funds.

Prevention

The most advanced protection tools are or include Firefox's tracking protection and the browser add-ons uBlock Origin and Privacy Badger. Moreover, they may include the browser add-on NoScript, the use of an alternative search engine like DuckDuckGo and the use of a VPN. However, VPNs cost money and as of 2023 NoScript may "make general web browsing a pain". On mobile, the most advanced method may be the use of the mobile browser Firefox Focus, which mitigates web tracking on mobile to a large extent, including Total Cookie Protection and similar to the private mode in the conventional Firefox browser. Users can also control third-party web tracking to some extent by other means. Opt-out cookies let users block websites from installing future cookies. Websites may be blocked from installing third-party advertisers or cookies on a browser, which will prevent tracking on the user's page. Do Not Track is a web browser setting that can request a web application to disable the tracking of a user. Enabling this feature will send a request to the website users are on to voluntarily disable their cross-site user tracking. Contrary to popular belief, browser privacy mode does not prevent (all) tracking attempts because it usually only blocks the storage of information on the visitor site (cookies). It does not help, however, against the various fingerprinting methods. Such fingerprints can be de-anonymized. Many times, the functionality of the website fails. For example, one may not be able to log in to the site, or preferences are lost. Some web browsers use "tracking protection" or "tracking prevention" features to block web trackers. The teams behind the NoScript and uBlock add-ons have assisted with developing Firefox's SmartBlock capabilities. Search Engines To safeguard user data from tracking by search engines, various privacy focused search engines have been developed as viable alternatives. Examples of such search engines include DuckDuckGo, MetaGer, and Swiscows, which prioritize preventing the storage and tracking of user activity. It's worth noting that while these alternatives offer enhanced privacy, some may not guarantee complete anonymity, and a few might be less user-friendly compared to mainstream search engines such as Google and Microsoft Bing.