Front-end development, also known as client-side development, is the practice of creating the visual and interactive elements of a website or application that users experience through their web browser. It involves writing HTML, CSS, and JavaScript code to build the user interface (UI) of a website or application.

Front-end developers are responsible for building the look, feel, and functionality of a website or application. They work with designers to create the layout and visual design, and they use programming languages to make the design come to life and add interactive features.

Front-end developers use a variety of tools, including text editors, version control systems, and browser developer tools, to write and test code. They also need to be proficient in web design principles and have a strong understanding of user experience (UX) design.