fldiff software package provides graphical diff program, 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 fldiff
fldiff is installed in your system.
Make ensure the fldiff package were installed using the commands given below,
$ sudo dpkg-query -l | grep fldiff *
You will get with fldiff package name, version, architecture and description in a table
| Distro | Ubuntu 16 04 lts xenial xerus |
| Section | Text Processing |
| Package | fldiff |
| Version | 1.1+0-3 |
| Description | graphical diff program |
| Sub Section | Text |