(all related links for downloading are in the 'Installing' section of this guide)
Vassal is a client-server platform that allows users to play board games over the internet. It has been launched in the mid-00's and there has been hundreds, if not thousands of various game modules over the years made by fans of those games. The X-Wing module is one of them and has seen the most volume of usage of all the games on that platform since 2016-2017.
A user typically has to install the client program of Vassal and the X-Wing module for it. It is possible that the Java Runtime Environment must be installed or updated as well on the computer. This means that the compatible operating systems are Windows, MacOS and a Unix based OS. ChromeOS (on Chromebooks or Android tablets) does not support Java.