Dapr is something of a Lego for building micro services. There is state management, pub/sub functionality and much more that you need for building micro services. Using Dapr you can focus on your business logic. Dapr can be used in a side car architecture, i.e you run Dapr side-by-side with your application without adding any dependencies to your application. Dapr can use gRPC (that was yesterdays topic) to communicate with.
Go check out the samples, the Distributed Calculator is awesome!