Spring boot is a light-weight framework that is majorly used to write microservices in Java. The primary advantage of spring-boot is that it enables auto-configuration for the project which reduces the burden on programmers and saves a lot of time.
It also makes use of annotations which are very simple and can replace the typical XML based configuration setup in spring MVC.
Spring boot also provides an embedded servlet container which makes it super easy to bootstrap(quick run) any web application that is production-ready without worrying about setting up a Tomcat server.
Along with all these benefits, the major benefit of using Spring boot is that it enables the creation of Fat jar for spring applications which has all the dependencies present inside on a single jar and hence you can directly run it.