While going through many answers on Unix & Linux, I came across many of them writing their contents and tags with POSIX or Bash or some other standard Linux shell.
I know of some differences like some of them have arrays and some do not, and other system level differences which I am not completely aware of.
Question Which one of them is the most widely used? Is there a long term benefit sticking to one over the other?
What are the things that matter for a Bash script writer to begin scripting in another shell?