HTTP cookie: Difference between revisions

Revision as of 11:12, 1 September 2023

Revision as of 09:51, 26 September 2023

Line 9:

Cookies serve useful and sometimes essential functions on the [[World Wide Web|web]]. They enable web servers to store [[program state|stateful]] information (such as items added in the shopping cart in an [[Online shopping|online store]]) on the user's device or to track the user's browsing activity (including clicking particular buttons, [[access control|logging in]], or recording which [[Web browsing history|pages were visited in the past]]).<ref>{{Cite web|title=What are cookies? What are the differences between them (session vs. persistent)?|url=https://www.cisco.com/c/en/us/support/docs/security/web-security-appliance/117925-technote-csc-00.html|id=117925|date=2018-07-17|website=Cisco|language=en}}</ref> They can also be used to save for subsequent use information that the user previously entered into [[Form (HTML)|form field]]s, such as names, addresses, [[password]]s, and [[payment card number]]s.

'''Authentication cookies''' are commonly used by web servers to [[Authentication|authenticate]] that a user is logged in, and with which [[Account verification|account]] they are logged in. Without the cookie, users would need to authenticate themselves by logging in on each page containing sensitive information that they wish to access. The security of an authentication cookie generally depends on the security of the issuing website and the user's [[comparison of web browsers#VulnerabilitiesSecurity and vulnerabilities|web browser]], and on whether the cookie data is [[Encryption|encrypted]]. [[Vulnerability (computing)|Security vulnerabilities]] may allow a cookie's data to be read by an [[Security hacker|attacker]], used to gain access to [[Personal data|user data]], or used to gain access (with the user's credentials) to the website to which the cookie belongs (see [[cross-site scripting]] and [[cross-site request forgery]] for examples).<ref name="UjTred">{{cite web |url=http://news.cnet.com/8301-10789_3-9918582-57.html |first=Robert |last=Vamosi |title=Gmail cookie stolen via Google Spreadsheets |website=News.cnet.com |date=2008-04-14 |access-date=19 October 2017 |archive-url=https://web.archive.org/web/20131209210402/http://news.cnet.com/8301-10789_3-9918582-57.html |archive-date=9 December 2013 |url-status=live}}</ref>

'''Tracking cookies''', and especially [[#Third-party cookie|third-party tracking cookies]], are commonly used as ways to compile long-term records of individuals' [[Web browsing history|browsing histories]] {{Em dash}} a potential [[Internet privacy#HTTP cookies|privacy concern]] that prompted European<ref name="mb6wv">{{cite web |title=What about the "EU Cookie Directive"? |url=http://webcookies.org/faq/#Directive |year=2013 |publisher=WebCookies.org |access-date=19 October 2017 |archive-url=https://web.archive.org/web/20171011095259/https://webcookies.org/faq/#Directive |archive-date=11 October 2017 |url-status=live}}</ref> and U.S. lawmakers to take action in 2011.<ref name="eulaw">{{cite news |url=https://www.bbc.co.uk/news/technology-12668552 |work=BBC |title=New net rules set to make cookies crumble |date=2011-03-08 |access-date=2018-06-21 |archive-url=https://web.archive.org/web/20180810220427/https://www.bbc.co.uk/news/technology-12668552 |archive-date=2018-08-10 |url-status=live}}</ref><ref name="KM1a4">{{cite web |url=http://adage.com/article/digital/sen-rockefeller-ready-a-real-track-bill/227426/ |work=Adage.com |title=Sen. Rockefeller: Get Ready for a Real Do-Not-Track Bill for Online Advertising |date=2011-05-06 |access-date=2011-06-02 |archive-url=https://web.archive.org/web/20110824225528/http://adage.com/article/digital/sen-rockefeller-ready-a-real-track-bill/227426/ |archive-date=2011-08-24 |url-status=live}}</ref> European law requires that all websites targeting [[European Union]] member states gain "[[informed consent]]" from users before storing non-essential cookies on their device.