PID 1

PID 1 is the first process launched when a Unix-like operating system boots up, acting as the main supervisor for all other processes. It is responsible for starting, managing, and shutting down system processes, including critical services. PID stands for "Process ID," a unique number assigned to each process, and 1 indicates it's the initial process assigned by the system kernel. Essentially, PID 1 ensures the operating system runs smoothly by overseeing other processes and handling system initialization and shutdown tasks.