First of all, this application is useful to gamers because it uses minimal amount of system resources, absolutely not affecting the FPS.
Discord allows you to organize online conferences with flexible communication channel, voice communication works on the principle of Push-To-Talk. The developers sought to create an application to communicate with low latency, which would include the best of other VoIP applications (like TeamSpeak and Skype).
The applications like Discord are used to improve coordination of teams/guilds in games, in situations when there is no possibility to write in chat to solve problems or just to have fun.
Installation latest version into Linux Mint:
1. Download DEB package
2. Double click, install
3. Run from menu