Progressive Web Apps use modern web capabilities to provide an app-like experience to users. They are responsive and work across all device types. PWAs aim to load quickly, even with uncertain network conditions. They also respond smoothly to user interactions without janky or laggy behavior. Features like the web manifest and service workers help make PWAs feel like native apps to users. Implementing strategies such as the PRPL pattern and following performance best practices from RAIL can help optimize PWAs. Case studies on Twitter and Alibaba found business benefits from users adding PWAs to their home screens, including increased engagement.