What are cookies?
Cookies are small text files that are stored in a user’s browser. Most cookie contains a unique identifier called a cookie ID: a string of characters that websites and servers associate with the browser that stores the cookie. This allows websites and servers to distinguish the browser from other browsers that store different cookies and to recognize each browser according to their unique cookie ID.
Cookies are widely used by websites and servers to provide many of the basic services available online. If you shop on a website, a cookie allows the web site to remember the items you’ve added to your virtual shopping cart purchases. If you set the preferences in a web site, a cookie allows the website to remember your preferences for your next visit. If you sign into a website, the latter might use a cookie to recognize your browser at a later time, so that you do not need to enter credentials to log in again. Cookies also allow websites to collect data about user activity, such as the number of unique visitors to a page every month. All these uses depend on the information stored in cookies.
The cookie ID in each DoubleClick cookie is essential for these uses. For example, DoubleClick uses cookie IDs to keep a log of ads to display on different browsers. When it’s time to publish an ad in a browser, DoubleClick can use the browser cookie ID to check which DoubleClick ads have already been shown by that particular browser. In this way, DoubleClick does not show users that have already been displayed ads. Similarly, cookie IDs allow DoubleClick to log conversions related to ad requests, such as when a user views a DoubleClick ad and later uses the same browser to visit the advertiser’s website and make a purchase.
DoubleClick cookies contain no personally identifiable information of users. With permission from the user, information associated with the DoubleClick cookie you can be added to your Google Account for that user.
If a user who has not logged chooses to proceed with disabling ads in the Settings section, the ID unique DoubleClick cookie in the user’s browser is overwritten with the phrase “OPT_OUT” and will not be used to personalize ads . Since there is no longer a unique cookie ID, the opt-out cookie can not be associated with a specific browser.
If a user who has logged chooses to proceed with disabling ads in the Settings section, the ID unique DoubleClick cookie in the user’s browser will not be overwritten. However, the DoubleClick cookie ID will not be used to personalize ads when the user logs on.
When cookies are sent to a browser by DoubleClick?
DoubleClick sends a cookie to the browser after impression, click, or other activities that result in a call to the DoubleClick servers. If your browser accepts cookies, it is stored in the browser.
Most commonly, DoubleClick sends a cookie to the browser when a user visits a page on which DoubleClick ads. Pages with DoubleClick ads include ad tags that indicate the browser to request content of ads in the DoubleClick ad server. When the server displays the content of ads, also sends a cookie. For this to happen, it is not necessary in a DoubleClick ads show page; just include DoubleClick ad tags, which might load one of the detection tool click or impression pixel.
Original cookies and third-party
Cookies are classified as original or third-parties for their potential association with the domain of the site visited by the user. Keep in mind that the name or the contents of the cookie do not change. Depending on the domain to which you can point your browser to determine whether the cookie is original or third-party.