Boot is just an embedded Tomcat/Jetty included with all the different Spring libraries. That makes for an easily bundled application (single executeable jar whi

Boot is just an embedded Tomcat/Jetty included with all the different Spring libraries. That makes for an easily bundled application (single executeable jar which launches the web server including all the application code). There are a lot of Spring libraries to learn about, but only a couple are actually required in a Spring boot app.