Check out example codes for "what can you do with java". It will help you in understanding the concepts better.
Code Example 1
Java is a very popular programming language. Some things you can do with it: 1) Make the backend of a website with spring (https://docs.spring.io/spring/docs/current/spring-framework-reference/") 2) Make an android application (https://developer.android.com/docs) 3) Make a simple desktop application with "JavaFX"
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