DOS Professionhood Practice Exam 2025 – Comprehensive Test Preparation

System calls serve a critical function in the interaction between user programs and the operating system. Their primary significance lies in enabling user applications to request services and resources from the operating system, which operates as an intermediary between hardware and software. When a program needs to perform tasks such as accessing files, managing memory, or handling input and output, it makes a system call. This effectively transitions control from the user program to the operating system, ensuring that these requests are handled securely and efficiently.

Through system calls, programs can perform essential operations that require privileged access to system resources, thereby maintaining the integrity and security of the operating environment. This interaction is crucial for the functioning of applications in DOS, as it allows them to utilize the system's capabilities, ultimately leading to a smoother user experience and robust software performance.