The significance of source code in software development lies in its foundational role in creating programs and applications. It serves as the set of instructions that defines how a software application operates. Access to source code allows developers to understand, modify, and improve the software, enabling collaboration and innovation. Additionally, source code management is essential for version control, ensuring that changes can be tracked and managed effectively. In essence, source code is vital for the maintenance and evolution of software systems, fostering a sustainable development environment.