What are the differences between Amazon Corretto and OpenJDK (and Oracle\'s OpenJDK - but there is already a ticket about this)? Corretto is a OpenJDK version 8 implementation.
From Amazon's description:
"Patches and improvements in Corretto enable Amazon to address high-scale, real-world service concerns, meeting heavy performance and scalability demands. We’re making these available to customers with no-cost, long-term support, with quarterly updates including bug fixes and security patches. AWS will also provide urgent fixes to customers outside of the quarterly schedule"
So Corretto has tweaks that are specific to performance (e.g. for server or cloud applications), and also additional bug fixes that users can take advantage of that aren't necessarily in OpenJDK proper yet. Also with this Amazon is offering proper LTS support of their build, as other commercial companies are starting to do for the JDK (Oracle and Azul come to mind, as well as others).