Licences for Physical Cores:

In this licensing mode, the cores of the physical machine are licensed. This allows for maximum performance of the physical machine and the Windows Server. It is also the most expensive option, as if a physical machine has many cores per processor, licensing them all requires several licences. You can also choose to license only a certain number of physical cores, but the server will not operate at the same processing speed as if all the cores are licensed.

With this option, you could license 16 cores or more, with the main license for 16 physical cores and Add On licenses for 2 cores. Now, this would be the most expensive option, which maximises the performance and speed of your servers.

Licence for Digital Cores:

With these licences, you can install a version that does not license the physical cores of the machine and that operates like a normal application, with less performance but still enough for most applications used with the Datacenter. You can also license virtual machines or Hyper-V Containers for companies that do not want to spend money on licensing the cores of the physical machine. These licences are more economical and offer a high level of performance in the virtual space.