Replacement for source in sh

Replacement for source in sh

bash shell sh dot-source

shell

"source" command in shell script not working [duplicate]

bash shell command-line-interface sh dot-source

shell

What's the difference between: ". [script]" or "source [script]", "bash [script] or $SHELL [script]", and "./ [script]" or "[script]"?

linux bash shell dot-source

shell