what is difference between extend, overlay and override component in aem

Question

What is the difference between Extending a component, overriding a component and overlaying a component. Can someone please explain with developer point of view

Bedlamite

@i.net, Thank you for your response. But I didn't get clarity between how to override and overlay OOTB component . – Bedlamite

Can you be more specific with your understanding of the concept? The override/overlay concepts are well discussed in other post I mentioned. – Yukikoyukio

@i.net, can you tell me how to override OOTB component in my project. I'm learning aem. Please help me. – Bedlamite

Just change the sling:resourceSuperType property of your component to override the behaviour of base component. – Yukikoyukio

I have added more details in answer below to be more specific. – Yukikoyukio

Possible duplicate of How to use/understand AEM Sling Resource Merger, override and Overlay concepts – Kalpak

@AnilJagtap may be help full aemvardhan.wordpress.com/2017/02/22/… – Lentil

Answer 1

Extend and Overlay are same. It's just a matter of terminology. Extending and overlaying involves copying the component from /libs/ (or other base library) to /apps node and changing the behaviour.

Override is similar to extend but the only difference is that you change the sling:resourceSuperType of the component so that it's behaviour completely changes (hence overridden).

More details can be found at:

https://docs.adobe.com/docs/en/aem/6-3/develop/components/components-basics.html

Yukikoyukio