Can you explain what is meant by annotation in programming?

In programming, annotations are special metadata added to code (classes, methods, variables, etc.) to convey additional information to the compiler, runtime environment, or development tools. Annotations do not directly affect the program's logic but can be used for automatic code generation, configuration, validation, or testing.

For example, in Java, the @Test annotation indicates that a method is a test and should be executed by a testing framework:

import org.junit.Test;

public class ExampleTest {
    @Test
    public void testMethod() {
        // test code
    }
}

Thus, annotations help make the code more expressive and manageable without changing its core logic.