Cookie syncing

<p>Cookie syncing, cookie synchronization or cookie matching is a technique in online advertising to <a href="/facts/Web_tracking/3cdL4NmX">track</a> users across multiple websites. Once users see an <a href="/facts/Online_advertising/Ncsv0GRz">advertisement</a>, user data in the form of <a href="/facts/HTTP_cookie/o1laXyng">cookies</a> is shared among ad companies, allowing them to link identifiers and create a user-specific profile to optimize <a href="/facts/Targeted_advertising/SsSEgQlt">targeted advertising</a>. The process increases the relevance of <a href="/facts/Personalized_marketing/YMxJvIJg">personalized ads</a> shown to the user, but raises <a href="/facts/Internet_privacy/Fdnjfnds">privacy concerns</a> in the way it enables companies to track people across the internet without their direct knowledge or explicit consent. Cookie syncing can also expose <a href="/facts/Personal_data/384PbBg5">personal information</a>, weaken <a href="/facts/Internet_security/LeTm8Wx4">security</a>, and is difficult for users to avoid, even if they attempt to delete cookies on their device. The practice is widespread among major advertising networks. In Europe, the <a href="/facts/General_Data_Protection_Regulation/RMLY6ohr">General Data Protection Regulation</a> led to a decrease in cookie syncing compared to the United States. 
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Cookie syncing open-in-new

Cookie syncing