I was lead to believe that there were no differences between aliases in zshrc and bashrc however, that appears to not be the case. I had an alias that would help me familiarize myself with the command line utilities available to me, but after copying it over to the new zshrc of mine, it fails to work. I have confirmed that it's not an error by changing the alias, which resolved the issue. The command is aliased to `?`. Why can I not use `?` when creating an alias? `alias ?='pwd'` `alias ?='echo hello'` amongst others have been attempted. No alias mapped to ? has worked, as mentioned. It is located in the ~/.zshrc file. I copied it from my .bashrc, as I have just decided to try zsh out.