Microservices
While there is no standard definition for microservices, most reference Martin Fowler's seminal paper1. To paraphrase, microservices are used to compose complex applications using "small", independent (autonomous), replaceable processes that communicate using lightweight, language-agnostic APIs.
If the terms sound familiar, they should. Each microservice in the simple example shown in Figure 1-1 is a twelve factor application, with replaceable backing services providing a message broker, service registry, and independent data stores. This reinforces the statement that having an understanding of the1.2, “Twelve factors” on page 2 will help you to create microservices.
1. “Microservices: A new architectural term”, Martin Fowler, http://martinfowler.com/articles/microservices.html ↩