The term "Controller" tends to be used interchangeably with the term "Data Controller", and has its routes in data protection regulations, such as the EU's GDPR (which has been incorporated into UK law after the UK's exit from the EU). It refers to individuals and companies which, alone or jointly with others, determine the purpose and means of processing people's personal data. It is common to see contracts which refer to the Controller in industries which deal with a lot of data such as Software-as-a-Service (SaaS) companies, marketing companies and other technology firms. Controllers are typically referenced alongside other terms found in data protection regulations, like the "Processor", "Data Subject", "Personal Data", "Personal Data Breach" and "Processing".
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