Operating Systems
User Space
Definition
User space, or userland, is the area in memory where user applications execute. It is a protected and less privileged environment compared to the kernel space.
Why It Matters
The separation between user space and kernel space is a fundamental security principle. It prevents user applications from directly accessing or corrupting critical OS components and hardware.
Contextual Example
Your web browser, text editor, and games all run in user space. If they need to perform a privileged action, like writing to a file, they must request it from the kernel via a system call.
Common Misunderstandings
- If a program in user space crashes, it typically does not affect the operating system kernel or other running applications.
- The CPU can operate in different modes, enforcing the boundary between user space and kernel space.