Autocompletion
Most shells allow you to autocomplete commands and arguments. If you press !kbd[Tab] the shell will try to autocomplete the command, or if there are multiple alternatives, print them. For example, writing r and then pressing !kbd[Tab] will give you all commands starting with r. When autocompleting arguments it will try to autocomplete to available files and folders.
Some shells require you to double-tap !kbd[Tab] to see all available alternatives.