to start explaining the microservice style it’s useful to compare it to the monolithic style: a monolithic application built as a single unit. enterprise applications are often built in three main parts: a client-side user interface (consisting of html pages and javascript running in a browser on the user’s machine) a database (consisting of many tables inserted into a common, and usually relational, database management system), and a server-side application. the server-side application will handle http requests, execute domain logic, retrieve and update data from the database, and select and populate html views to be sent to the browser. this server-side application is a monolith - a single logical executable. any changes to the system involve building and deploying a new version of the server-side application.