What are Subshells in Linux

In Linux, every time you open a terminal, you start a shell, usually Bash or Zsh. But what happens when you run a command inside parentheses, like this?

$ (pwd; ls)

You’ve just created a subshell, a new child shell that runs your commands in isolation from the parent. Subshells are one of those shell concepts that quietly do a lot behind the scenes in B…