Hosting images in amazon s3

Hello,

I know that wp automatically creates duplicates images of the uploaded one, when theme or some plugin shows them in different size.. am I right?
I’m going to move my images from wp-content/uploads to amazon s3, I don’t use any plugin, just move the images from my hosting provider to s3. Now.. do I must move all the already duplicated images in s3 too? and what will happens for the new images uploaded in s3? will duplicates be generated in s3 too? or, any visualization incompatibility?

Thanks in advance for who will be able to let me understand how wp works for images hosted in external server.

Regards