fish software package provides friendly interactive shell, you can install in your Ubuntu 16.04 LTS (Xenial Xerus) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install fish
fish is installed in your system.
Make ensure the fish package were installed using the commands given below,
$ sudo dpkg-query -l | grep fish *
You will get with fish package name, version, architecture and description in a table
| Distro | Ubuntu 16 04 lts xenial xerus |
| Section | Shells |
| Package | fish |
| Version | 2.2.0-3 |
| Description | friendly interactive shell |
| Sub Section | Shells |