A process (parent) can execute another process (child). When a parent process is killed all the child processes are automatically killed. The main system process that is started first is numbered as 1. If this process is killed the system will shutdown.
To see the tree of processes, you can use the command
A user can kill only the processes that the user has executed not the processes of other users. Only root can kill the processes of other users.
15 Create File
17 Copy File