Why Spring Boot created?
There was lot of difficulty to setup Hibernate Datasource, Entity Manager, Session Factory, and Transaction Management. It takes a lot of time for a developer to set up a basic project using Spring with minimum functionality.
What Spring Boot does?
Spring Boot does all of those using AutoConfiguration and will take care of all the internal dependencies that your application needs — all you need to do is run your application. It follows “Opinionated Defaults Configuration” Approach to reduce Developer effort.Spring Boot looks at a) Frameworks available on the CLASSPATH b) Existing configuration for the application. Based on these, Spring Boot provides basic configuration needed to configure the application with these frameworks. This is called Auto Configuration.
How to use Spring Boot ?