What is a system call? Give an example.

A system call is like a request to the operating system for help. For example, when a program wants to open a file, it asks the operating system using a system call.

What is the purpose of the process scheduler in an operating system?

The process scheduler decides which program gets to use the CPU next, making sure everyone gets a fair turn.

Explain the difference between preemptive and non-preemptive scheduling.

Preemptive scheduling lets the operating system interrupt a program and switch to another. Non-preemptive scheduling doesn’t interrupt until the program is done.

What is a deadlock in the context of operating systems?

Deadlock is like a traffic jam for computer programs. It happens when programs are waiting for each other to finish, but they can’t.

How does virtual memory work, and why is it important?

Virtual memory helps your computer use more memory than it physically has. It stores some data on the hard drive temporarily, which is important for running big programs.

What is a file system? Name a common file system used in modern operating systems.

A file system is like a filing cabinet for your computer’s files. One common file system is NTFS for Windows.

What is the role of the kernel in an operating system?

The kernel is the heart of the operating system. It manages hardware, memory, and all the important tasks.

Describe the difference between a monolithic and microkernel-based operating system.

Monolithic systems put everything together, while microkernel systems keep things separate for better stability and security.

What is a page fault, and how is it handled by the operating system?

A page fault is like forgetting where something is. The operating system finds the missing piece on the hard drive and brings it back to memory.

Explain the concept of file permissions in Unix-like operating systems.

File permissions are like locks on doors. They decide who can read, write, or execute a file. Unix uses symbols like “rwx” for these permissions.

What is a semaphore, and how is it used for synchronization in operating systems?

A semaphore is like a traffic signal for programs. It helps them take turns and avoid conflicts when using shared resources.

What is the purpose of the I/O scheduler in an operating system?

The I/O scheduler manages input and output tasks, like reading from a hard drive. It decides which task should go next to keep things efficient.