How Linux commands are executed in the background

When a process is not a daemon, it is not easy to add a & after the command line, and the process shuts down when the terminal shuts down. Since the process usually in the terminal start its parent process is the terminal process. When the terminal is closed, all its child processes are also closed. Making the process perform in the background requires the use of the Nohup command:

Nohup command > Out.log 2>&1 &

The role of Nohup is to set the parent process of the process to 1, the Init process, so that the process is not affected when the terminal shuts down.

The standard error output is also redirected to standard output using 2>&1, because the predefined stdin,stdout,stderr are 0,1,2 respectively.

How Linux commands are executed in the background