Through these buttons, sites can track and build a so-called “shadow profiles” on you even if you don’t click on them, even if you aren’t logged into any of the sites in question.
Definitions
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‘profiling’ means any form of automated processing of personal data consisting of the use of personal data to evaluate certain personal aspects relating to a natural person, in particular to analyse or predict aspects concerning that natural person's performance at work, economic situation, health, personal preferences, interests, reliability, behaviour, location or movements;
‘profiling’ means any form of automated processing of personal data consisting of the use of personal data to evaluate certain personal aspects relating to a natural person, in particular to analyse or predict aspects concerning that natural person's.....personal preferences, interests, reliability, behaviour, location or movements