A process is a running instance of a program with its own memory space and resources.
Key commands:
ps aux: List all processes with detailstop/htop: Real-time process monitoringstrace: Trace system calls a process makeslsof: List open files and network connections
Common interview questions:
- "What's the difference between a process and a thread?"
- "How would you find which process is using port ?"
- "What is a zombie process and can you kill it?"
A zombie process has completed execution but its parent hasn't read its exit status. You can't kill it directly. The parent must call wait().