Understanding orchestration concepts is key in this chapter so that we can learn more about Docker Swarm or Kubernetes. Let's imagine an orchestra: there are violinists, pianists, percussionists, and so on; every player has studied for many years to become a professional musician. They can play alone perfectly, but things get difficult when we add more instruments. Players can read the musical score and each one will play their part. But even the best musicians need someone to guide them when they're playing together. The orchestra director is key to making all the instruments work together.
When we divide our applications into small pieces – microservices – orchestration is required. An application requires a lot of components to work together. Remember that splitting a monolithic application into different functionalities also creates a new development workflow. We can have different groups of developers working who are focused...