What is the difference between Customer, Employee and Partner communities?

Hi Hazel,

Employee Community builds an internal social intranet across an enterprise. It includes Chatter, Sites, myCases, Answers, Files, Content Libraries, Knowledge, and Ideas.

Externally facing Community Cloud products include Customer Community, Customer Plus Community, and Partner Community. Customer Community enables feed discussions, groups, profiles, gamification, moderation, analytics — everything you need for high-scale external collaboration. Customer Community Plus adds the ability to control sharing; add private groups; and limit the ability to access files, posts, and records within the community so that some conversations can happen in private. In addition to this privacy, Partner Community enables cooperative selling within the community, adding lead and opportunity management, campaigns, and events.
Thanks