What Is Spring Boot?
Spring Boot is the framework behind most modern Java backends -- here's what it actually does and why it exists.
What Is Spring Boot?
Spring Boot is a framework built on top of the core Spring Framework that removes most of the manual setup Spring traditionally required. Instead of hand-writing XML configuration and wiring beans yourself, Spring Boot auto-configures your application based on what's on the classpath, ships an embedded web server (Tomcat by default), and gets a working REST API running from a single main() method.
Key Features
- Auto-configuration -- Spring Boot inspects your dependencies and wires up sensible defaults automatically
- Embedded server -- no separate Tomcat/Jetty install; the server ships inside your executable JAR
- Starter dependencies -- one line like spring-boot-starter-web pulls in everything needed for a web app
- Production-ready defaults -- health checks, metrics, and externalized configuration via Actuator
- No required XML -- configuration is Java-based or a simple application.properties file
What Is Spring Boot Used For?
Spring Boot is the default choice for building REST APIs, microservices, and enterprise backend systems in Java. Companies use it because it cuts the boilerplate that made older Spring (and Java EE) projects slow to start, while still giving you the full Spring ecosystem -- Spring Data for databases, Spring Security for auth, Spring Cloud for distributed systems -- when you need it.