Discord is a free voice and text communication platform targeted primarily at the gaming market. It aims to match the ease of use of existing chat clients like Skype and mix it with the power of servers with multiple rooms and role permissions offered by voice clients like Teamspeak.
Ranked in these QuestionsQuestion Ranking
Pro User friendly
Discord follows the same type of interface design popularised by Slack, which is extremely clean and attractive, and doesn't clutter the interface with unnecessary chrome and cruft.
Pro Can be used in browser
Users can invite others to join a Discord channel via a web link, which means no installation is required to use the software - which is one of the big typical barriers to entry for social software.
Pro Free for unlimited users
Pro Easy setup
You can quickly send invites to people and they can join in using the web client without having to create an account or install the app.
Pro Good 1-click invite system
Discord allows inviting people to a specific channel with a link. Links can be set to expire. Low effort/passive invite mechanics.
Pro Game integration
Discord shows which game each user is currently playing, which among other things helps users to form PUGs with minimal hassle.
Pro Has low-latency VoIP support
Pro Familiar for Slack users
For those that are used to the way Slack (a similar chat client) works, Discord will be familiar in its use, which lowers the learning curve quite a bit for those that have switched or tried Slack before.
Pro Open source bots and management tools
Discord has a wide variety of bots for things from airhorn noises to automated server management, to leveling systems for chat. The bot API is open and there are dedicated sites for finding bots.
Pro Supports video and text communication
Behaves and looks like Slack for regular text channels, but with the ability to create voice channels as well
Pro Android app has push notifications
Pro DDoS mitigation
Discord prevents users from being DDoSed out of games.
Pro Low effort invite mechanics
Pro Syntax highlighting and Markdown support
The support is limited but still exists. It's a killer feature for dev teams.
Pro Numerous controls for setting member roles.
Deny access, Deny write message, Allow read messages etc.
Pro Targeting of roles
Targeting roles allows for quickly requesting someone from a group e.g. artist, moderator, etc.
Con No self-hosting avaliable
Discord is wholly hosted by Discord (the company), you cannot run private instances, and all servers are hosted on their infrastructure. For most people, this won't really impact their usage.
Con Proprietary software
Discord is closed-source, meaning their code isn't available for inspection or reproduction
Con Not a generic "team chat" tool
All the UI and the features are aimed specifically at communicating with your gaming team/clan.