Can somebody explain the connection between Identity and IdentityServer?
There was a recent article that says there will be a new version of IdentityServer (ie IdentityServer 4).
I'm doing a ASP.NET 5 project. I only heard of Identity 3 before and I'm planning to use it.
Can I use Identity 3 in my project without using this IdentityServer?
There's no direct connection: ASP.NET Identity is a membership provider (i.e a way to manage your users) while IdentityServer is an OAuth2/OpenID Connect server you can use to support token authentication.
That said, IdentityServer4 will eventually support ASP.NET Identity 3 as a membership store.
Sure, you can use ASP.NET Identity without IdentityServer (and vice versa).