A full-stack developer is a professional skilled in both front-end and back-end web development, capable of creating and managing entire software applications. On the front end, they work with technologies like HTML, CSS, and JavaScript to design user interfaces. Simultaneously, on the back end, they handle server-side scripting, databases, and server infrastructure using languages such as Python, Ruby, or Node.js. Full-stack developers possess a holistic understanding of the software development process, enabling them to seamlessly navigate both client-side and server-side aspects, resulting in comprehensive and efficient application development.