Spring Boot will automatically configure a web application when it finds the classes on the classpath. It will also start an embedded server (by default it will launch an embedded Tomcat)1
3.1 Getting Started with Spring MVC
Problem
You want to use Spring Boot to power a Spring MVC application.
Solution
Spring Boot will do auto-configuration for the components needed for Spring MVC. To enable this, Spring Boot needs to be able to detect the Spring MVC classes on its classpath. For this you will need to add the spring-boot-starter-web as a dependency.