Functions are programs written in the fish syntax. They group together one or more commands and their arguments using a single name. It can also be used to start a specific command with additional arguments. The first line tells fish that a function by the name of ll is to be defined.
fish is a fully-equipped command line shell (like bash or zsh) that is smart and user-friendly.
fish supports powerful features like syntax highlighting, autosuggestions, and tab completions that just work, with nothing to learn or configure.
If you want to make your command line more productive, more useful, and more fun, without learning a bunch of arcane syntax and configuration options, then
fish might be just what you’re looking for!