In the vast digital ecosystem, Google and Facebook emerge as architects of data collection, each with a distinct blueprint for understanding user behavior. This talk will dissect Google's approach of embedding itself into every facet of life through a diverse suite of applications, capturing nuanced details of user interactions and preferences. Conversely, Facebook's strategy is twofold: deciphering desires and interests through the lens of social interactions, likes, and shares, and quietly monitoring users' digital footprints beyond its own platforms via "off Facebook activity." This session aims to peel back the layers of these sophisticated strategies and open minds on future trends on data harvesting.