elpa-circe software package provides client for IRC in Emacs, 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 elpa-circe
elpa-circe is installed in your system.
Make ensure the elpa-circe package were installed using the commands given below,
$ sudo dpkg-query -l | grep elpa-circe *
You will get with elpa-circe package name, version, architecture and description in a table
| Distro | Ubuntu 16 04 lts xenial xerus |
| Section | Network |
| Package | elpa-circe |
| Version | 2.1-2 |
| Description | client for IRC in Emacs |
| Sub Section | Net |