Real-time libraries are software libraries that allow developers to create applications that can interact with data in real-time. These libraries provide a set of APIs and tools for developers to build applications that can respond quickly to changes in data. They are commonly used in frontend development for creating interactive user interfaces, such as chatbots, live streaming services, and real-time analytics dashboards. Real-time libraries enable developers to create dynamic web experiences by providing access to data streams from various sources such as databases, message queues, and web sockets.