The frontend is the part of a software application that users directly interact with, typically through a web browser or mobile interface. It handles visual layout, UI behavior, and client side logic. Frontend code retrieves data from APIs and renders it so users can read, navigate, or manipulate information. Technologies like HTML, CSS, and JavaScript form the backbone of most modern frontends. Because frontends run on user devices, they must account for varying screen sizes, performance limitations, and network quality. The frontend collaborates closely with the backend, which provides data and business logic. A great frontend feels fast, responsive, and intuitive, even when the underlying systems are complex.
key characteristics
Frontends often use frameworks that manage state, routing, and component structures. Browsers enforce strict security boundaries that influence how frontends store data and communicate over the network. Frontend code must handle errors gracefully, especially when network latency or offline conditions occur. Performance optimization plays a major role because slow frontends quickly frustrate users. Frontend and backend teams coordinate on data schemas, endpoints, and authentication flows. When working with AI tools, explicitly describing UI requirements helps generate consistent components and interactions.