Question

I’m very new to shell scripting. I have a basic doubt of what is the use of & in shell scripting? That is doing something like this :

commands arg &

Waits to give more input. But what is its exact use? How should I use it in real world?

Answer 1

As you have used it there, it runs commands arg in the background, disconnected from your keyboard, and the shell immediately asks you for its next command.

As for the real world, I use it when I have a command that will take some significant time to run but does not require any input from me and will put all of its output into a file, for example

# walk through the whole filesystem looking for a particular filename
find / -name 'obscure.filename' -print > /tmp/found-it &