Serverless functions, exemplified by Pusher Serverless Functions, offer developers a way to enhance efficiency, scalability, and cost-effectiveness in building realtime experiences by focusing on business logic rather than server management. These functions support event-driven architectures, allowing applications to handle high concurrency and scale on demand, crucial for realtime messaging and data processing. By eliminating the need for infrastructure management, developers can dedicate more time to programming, optimizing resources through a pay-as-you-go model. Serverless functions are especially beneficial in applications such as chat apps and dashboards by automating processes, enabling event-driven actions, and offering seamless scalability. They also provide potential cost savings by reducing server management expenses and are adaptable to various use cases, including security, moderation, and integration with third-party services. As technology evolves, serverless functions are expected to integrate with edge computing, AI, and machine learning, promising more intelligent and automated applications. Pusher Serverless Functions specifically, hosted on Pusher's infrastructure, can be integrated with Pusher Channels to handle events like client or presence channel events, enhancing functionalities with features such as encryption and user authentication.