Software developers design, program, build, deploy and maintain software using many different skills and tools. They also help build software systems that power networks and devices and ensure that those systems remain functional. Programming Languages: Master one or more programming languages such as Python, Java, JavaScript, C++, or C#. Data Structures and Algorithms: Understand fundamental data structures (e.g., arrays, linked lists, stacks, queues) and algorithms (e.g., sorting, searching, graph algorithms).