After someone mentioned Alma Linux to me, it seemed similar to Rocky Linux, and I wondered why there would be two Linux distros doing the same thing (picking up from CentOS and remaining RHEL compatible).
I read that "Rocky Linux is a 1-to-1 binary to RHEL while AlmaLinux is Application Binary Interface-compatible with RHEL".
Wow. Now, not only did I learn about a new Linux distro, but I also have to run down what an Application Binary Interface, or ABI is.
Referring to this, Stack Exchange post: https://stackoverflow.com/questions/2171177/what-is-an-application-binary-interface-abi, I liked this "oversimplified summary":
API: "Here are all the functions you may call."
ABI: "This is how to call a function."
