Let's quickly define what we mean when we use the term microservice.
As the word already gives away, microservice consists of micro and service. Micro is smaller than small. A microservice by definition should be as small as possible. The other word, service, refers to the function of a microservice: it should do something for us. In this book—and in general—we call them microservices, the plural form of microservice. We do that because a microservice usually operates together with other microservices. A microservice application consists of multiple microservices working together and alongside each other.
Almost all major players, such as Google, Amazon, and Facebook, started out as so-called monolithic applications. What does that mean? In essence, a monolith is an application that operates as one large code base. Popular examples include...
