In the world of web development, a Full-Stack Developer is someone who possesses the skills to work on both the front-end and back-end of a web application. These developers are well-versed in all layers of web development, from designing and implementing the user interface (UI) to managing databases, servers, and APIs that power the application. Full-stack developers have a comprehensive understanding of how both sides of a web application function and are capable of building complete, end-to-end solutions.