A software developer is a professional who designs, codes, tests, and maintains software applications or systems. They work with programming languages, tools, and frameworks to build software that meets user needs and business objectives. This role requires problem-solving skills, a strong understanding of computer science principles, and the ability to work collaboratively in teams. Developers often specialize in areas such as web development, mobile applications, or systems programming, and they may work across various industries including technology, finance, healthcare, and entertainment.