It is a sidecar which sits alongside your application. You can access it via http or grpc. They additionally provide multi-language sdks for it. Think database

It is a sidecar which sits alongside your application. You can access it via http or grpc. They additionally provide multi-language sdks for it. Think database + sdks but for distributed systems. Most importantly to me, it offers both REST and interface-based programming models allowing the consumer to decide how they want to operate with it.