有人可以解释ivy.xml依赖的conf属性吗？

<ivy-module version="2.0">
    <info organisation="com.example" module="my-module"/>

   <configurations>
        <conf name="compile" description="Compile dependencies"/>
        <conf name="test" description="Test dependencies" extends="compile"/>
    </configurations>

   <dependencies>
       <dependency org="org.slf4j" name="slf4j-api" rev="1.7.30" conf="compile->default"/>
       <dependency org="junit" name="junit" rev="4.13.1" conf="test->default"/>
    </dependencies>
</ivy-module>