Final answer:
The init process on Unix is responsible for starting and managing all other processes. It also cleans up resources used by terminated processes.
Step-by-step explanation:
The init process, also known as the first process, is responsible for starting and managing all other processes on a Unix system. It is assigned Process ID (PID) 1 and is the ancestor of all other processes.
When a process terminates on Unix, the init process is responsible for cleaning up resources used by that process. It reaps the terminated process and updates the process table accordingly.
For example, if a user runs a command and it completes or is terminated, the init process will remove the process entry from the process table, making resources available for other processes.