If you have multiple microservices are required to interact each other and if you want to interact them without any dependency or make loosely coupled, than we should use Asynchronous message-based communication in Microservices Architecture. Because Asynchronous message-based communication is providing works with events. So events can place the communication between microservices. We called this communication is a event-driven communication.

That means if any changes happens in the Domains of microservices, it is propagating changes across multiple microservices as an event after that these events consumed by subscriber microservices. This event-driven communication and asynchronous messaging brings us “eventual consistency” that we will discuss this in the upcoming articles.

https://medium.com/design-microservices-architecture-with-patterns/microservices-asynchronous-message-based-communication-6643bee06123