Actually, there are 4 versions that will run on a PC—two you mentioned; Home and Pro.
Windows 10 Enterprise, which is the volume license product used by corporations and businesses, and has several domain-level features such as DirectAccess, Bitlocker, AppLocker and BranchCache.
Windows 10 Education will be very similar to Enterprise but will have a cheaper volume license for Academic institutions. Teachers and students with Home or Pro may be eligible to upgrade to Education.
Another is Windows 10 Mobile, for phones.
Finally, there is the Windows 10 IoT Core. IoT is Internet of Things, and is an embedded operating system for various devices such as point of sale registers, Raspberry Pi devices, and other controller type functions—which may expand into appliances and other household products, as well as manufacturing control units.
So yeah, there are six versions. But as you point out, each version will have a special ability and will be used depending on requirements.
I would recommend all businesses get Enterprise, which, while more expensive, allows unlimited installations (with a KMS license), and home users get Pro. For a few dollars more, Pro will give you more features and can handle more memory and two separate, physical processors.
And only two of those will apply to an average consumer PC purchase.