Communities are groups of people that gather together in real-time based on shared interests. Often times theses interests are based on a particular genre of music. The list of communities are sorted by the number of other people currently active in a given community at any given point in time. Each row also displays the name of the song or video that everyone in the community is currently listening to. If any of your friends are currently active in a given community you can see how many. Just click on the name of any community that sounds interesting and you will join the party. You can also create your own community, but we recommend for your first time that you join a few established communities first to see how they operate.