Cookies, also known as browser cookies or tracking cookies, are small, often encrypted text files, located in browser directories. They are used by web developers to help users navigate their websites efficiently and perform certain functions. Due to their key role of enhancing/enabling usability or site processes, disabling cookies may prevent users from using certain websites. Every time a user loads a website, the browser sends the cookie back to the server to notify the website of the user's previous activity. Cookies are designed to be a reliable mechanism for websites to remember useful information (such as items in a shopping cart) or to record the user's browsing activity (including clicking particular buttons, logging in, or recording which pages were visited by the user as far back as months or even years ago).
Cookies are used for a number of purposes – some types of cookies perform essential authentication function as they help web servers recognize whether the user is logged in or not, and which account they are logged in with.
Cookies can be used to remember information about the user in order to show relevant content to that user over time. For example, a web server might send a cookie containing the username last used to log into a website so that it may be filled in automatically the next time the user logs in.
Some cookies (tracking cookies) are used to track users' web browsing habits. This can also be done to some extent by using the IP address of the computer requesting the page or the referrer field of the HTTP request header, but cookies allow for greater precision.
A cookie will typically contain the name of the domain from which the cookie has come, the "lifetime" of the cookie, and a value, usually a randomly generated unique number.
Browsers, nowadays, use different types of cookies such as:
A session cookie, also known as an in-memory cookie, exists only in temporary memory while the user navigates the website. Web browsers normally delete session cookies when the user closes the browser. Unlike other cookies, session cookies do not have an expiration date assigned to them, which is how the browser knows to treat them as session cookies.
Instead of expiring when the web browser is closed as session cookies do, persistent cookies expire at a specific date or after a specific length of time. This means that, for the cookie's entire lifespan (which can be as long or as short as its creators want), its information will be transmitted to the server every time the user visits the website that it belongs to, or every time the user views a resource belonging to that website from another website (such as an advertisement).
A secure cookie can only be transmitted over an encrypted connection (i.e. HTTPS). This makes the cookie less likely to be exposed to cookie theft via eavesdropping.
Normally, a cookie's domain name will match the domain name that is shown in the web browser's address bar. This is called a first-party cookie. Third-party cookies, however, belong to domains different from the one shown in the address bar. These sorts of cookies typically appear when web pages feature content, such as banner advertisements, from external websites. This opens up the potential for tracking the user's browsing history, and is often used by advertisers in an effort to serve relevant advertisements to each user.
As some cookies can be a potential security concern most modern web browsers contain privacy settings that can block third-party cookies.
Most modern browsers support cookies and allow the user to disable them. The users have the following common options:
Add-on tools for managing cookie permissions also exist.
There are generally four categories of cookies this site uses: “Strictly Necessary”, “Performance”, “Functionality” and “Targeting”. This site routinely uses all four categories of cookies on the Service. You can find out more about each cookie category below.
1. Strictly Necessary Cookies. These cookies are essential, as they enable you to move around the Service and use its features, such as accessing logged in or secure areas.
3. Functionality Cookies. These cookies allow us to remember how you’re logged in, whether you chose to no longer see advertisements, whether you made an edit to an article on the Service while logged out, when you logged in or out, the state or history of Service tools you’ve used. These cookies also allow us to tailor the Service to provide enhanced features and content for you and to remember how you’ve customized the Service in other ways, such as customizing the toolbars we offer in the right column of every page. The information these cookies collect may be anonymous, and they are not used to track your browsing activity on other sites or services.
4. Targeting Cookies. Our advertising partners or other third party partners may use these types of cookies to deliver advertising that is relevant to your interests. These cookies can remember that your device has visited a site or service, and may also be able to track your device’s browsing activity on other sites or services other than this site . This information may be shared with organizations outside this site, such as advertisers and/or advertising networks to deliver the advertising, and to help measure the effectiveness of an advertising campaign, or other business partners for the purpose of providing aggregate Service usage statistics and aggregate Service testing.