A back-end developer writes code that forms the backbone of a website or app. Learn more about this career field and how to get started. Ever wonder what goes on behind the scenes of a website? How, exactly, does clicking on a button take you to a different page? And where does your personal information go when you sign up for a free trial? Back-end developers are the experts who build and maintain the mechanisms that process data and perform actions on websites. Unlike front-end developers, who control everything you can see on a website, back-end developers are involved in data storage, security, and other server-side functions that you cannot see. Since the late 80s and 90s, the internet has transformed the way humans access information, and web development has continued to evolve. Its central importance to our digital world means web developers are in high demand. Fortunately, anyone can learn the technical skills needed to be front-end, back-end, or full-stack (both front- and back-end) developers.