Spring Boot is a Java framework designed to simplify the development of applications based on the Spring Framework, eliminating much of the manual configuration. It aims to speed up the project startup and configuration process, providing a robust and efficient environment for developers.

One of Spring Boot's most notable features is autoconfiguration, which automatically detects the dependencies present in the project and configures the necessary components without explicit intervention. This significantly reduces configuration time and allows developers to focus more on business logic.

Another important advantage is the built-in server. Unlike solutions like Java EE, which require the configuration and management of an external server, Spring Boot already includes a server by default, like Tomcat, allowing applications to run independently without the need for manual configuration of an application server.

In addition, Spring Boot provides a series of "starter dependencies", which facilitate the initial configuration of various processes. A popular example is spring-boot-starter-web, used to create web applications in a simplified way.

Spring Boot also stands out for its use of annotations that make project configuration even more intuitive. Some of the main annotations are:

@SpringBootApplication
Spring Boot's core annotation, which combines several functionalities such as @Configuration, @EnableAutoConfiguration, and @ComponentScan. It is used in the main class to initialize the application.

@RestController
It unites @Controller and @ResponseBody, making it easier to create REST controllers. Methods annotated with @RequestMapping or equivalent return data directly, rather than from HTML pages.

@RequestMapping
Used to map HTTP requests to specific methods. It can be configured for different types of requests, such as GET, POST, PUT and DELETE.

@Autowired
Performs automatic dependency injection in classes managed by Spring. However, it should be used with caution to avoid excessive coupling between different layers of the application.

@Service
Marks a class as a service component, generally used to encapsulate the application's business logic.

@Repository
Identifies a class as a repository, which manages access to persisted data, typically using JPA or other persistence technology.

@EnableAutoConfiguration
Instructs Spring Boot to automatically configure the application context based on the dependencies present in the project.

Spring Boot is a powerful tool that simplifies Java application development by automating most of the configuration and providing a self-sufficient runtime environment with built-in servers. Its features such as autoconfiguration, starter dependencies and annotations make the development process much more agile and efficient. In this way, Spring Boot establishes itself as an ideal choice for developers looking for speed, flexibility and ease of maintenance in their Java applications.