What is a microservice?

Companies worldwide have used the microservice architecture model so widely that it has almost become a default way of software development. Those companies have tens, hundreds, and even thousands of microservices at their disposal.

So, what exactly is the microservice model?

The microservice architecture model is organizing an application as a collection of services, called microservices, each of which is further responsible for a certain part of application logic, usually defined by a particular business capability.

As an example, consider an online marketplace application. The application may have multiple features, including search, shopping cart, payments, order history, and many more. Each feature can be so different that the code may (and, in certain cases, should) be completely independent of the rest of the application. In this example, search and payments technically have nothing in common. In the microservice architecture model, each component would be an independent service playing its own role in the system.

Organizing each part of the application as a separate service is not necessarily a requirement. As with any architecture model or any aspect of software development, engineers need to be careful with choosing a particular approach or solution – doing an initial analysis and understanding the solution under the given conditions.

Before we proceed to the key benefits and downsides of microservices, let's see what challenges you could face when the application is not separated into multiple services.