How do I run a Unix script in parallel?

You have various options to run programs or commands in parallel on a Linux or Unix-like systems: => Use GNU/parallel or xargs command. => Use wait built-in command with &. => Use xargs command.

How do I run a parallel script?

To run script in parallel in bash, you must send individual scripts to background. So the loop will not wait for the last process to exit and will immediately process all the scripts.