Hi emacs users, the eshell.text file as of current emacs master contains the following paragraph: The command can be either an Elisp function or an external command. Eshell looks first for an @ref{Aliases, alias} with the same name as the command, then a @ref{Built-ins, built-in command} or a function with the same name; if there is no match, it then tries to execute it as an external command. With makeinfo version 6.3 this renders nicely in html: