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: • pages and content a user browsed, • what a user searched online, • when a user clicked on an online advertisement, • what time a user visited a site.
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
CNAME cloaking, 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 •
Canvas fingerprinting allows websites to identify and track users using HTML5 canvas elements instead of using a browser cookie. •
Cross-device tracking are used by advertisers to help identify which channels are most successful in helping convert browsers into buyers. •
Click-through rate is used by advertisers to measure the number of clicks they receive on their ads per number of impressions. •
Mouse tracking collects the user's mouse cursor positions on the computer. •
Browser fingerprinting relies on your browser and is a way of identifying users every time they go online and track your activity. Through fingerprinting, websites can determine the user's operating system, language, time zone, and browser version without your permission. •
Supercookies or "
evercookies" can not only be used to track users across the web, but they are also hard to detect and difficult to remove since they are stored in a different place than the standard cookies. •
Session replay scripts allows the ability to replay a visitor's journey on a
web site or within a
mobile application or
web application. • "Redirect tracking" is the use of
redirect pages to track users across websites. •
Web beacons are commonly used to report that an individual who
received an email has read it. •
Favicons can be used to track users since they persist across browsing sessions. •
Federated Learning of Cohorts (FLoC), trialed in
Google Chrome in 2021, which intends to replace existing behavioral tracking which relies on tracking individual user actions and aggregating them on the server side with web browser declaring their membership in a behavioral cohort.
EFF has criticized FLoC as retaining the fundamental paradigm of
surveillance economy, where "each user's behavior follows them from site to site as a label, inscrutable at a glance but rich with meaning to those in the know". • "UID smuggling" (method of tracking users on the Internet that allows user identifiers (UIDs) to be synchronized across different sites) was found to be prevalent and largely not mitigated by latest protection tools – such as
Firefox's tracking protection and
uBlock Origin – by a 2022 study, which also contributed to countermeasures. == Browsers ==