In the context of designing a real-time analytics system for a global e-commerce platform, you are tasked with processing high-velocity streaming data to provide insights on user behavior. The system must handle data from millions of users worldwide, with the requirement to process and analyze data in near real-time to personalize user experiences dynamically. Considering the need for scalability, cost-efficiency, and compliance with global data protection regulations, which of the following best describes the role of 'window' in streaming data processing within this scenario? Choose the best option.