'sh' shell - Actually calls legacy Bourne shell, or uses system default?
While answering a question, I came across a gap in my own knowledge. Now, I've picked up from somewhere that the 'sh' shell (specifically, if you select it as your login shell) is essentially a symlink to the system default shell, usually bash. However, while double-checking this before posting along these lines, I found web pages claiming that it's still installed on all Linuxes, and implying that it's called if the shabang in a script is /bin/sh. Can someone take the time to confirm for me what the 'sh' shell does in various situations?
Thanking you in advance,