Yes, Spring Boot allows you to use both, and environment variables take precedence over properties defined in `application.properties`. Q. What is the difference between `application.properties` and `application.yml`? A. Both serve the same purpose, but `application.yml` offers a more readable format for hierarchical data using indentation. Q.

https://codingtechroom.com/tutorial/java-spring-boot-properties-env-variables

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