To launch a shell in Emacs, you can use M-x shell. However, when you want to launch another one, you have to name the second shell.

I usually don’t care much about naming shells, so I use this bit of code to launch a new shell. It creates a new shell and gives it a unique name. I named it “newsh”, so you can run it with M-x newsh. Here’s the function:

(defun newsh ()
"Run a new shell and rename it uniquely."
(interactive)
(save-excursion
  (shell)
  (rename-uniquely)))