Question about HP Thin Client T430

According to various other online shops, this device with the model number 3VL60AA#UUZ (evident in the specs) does not run on Windows, but an HP distro of Linux called "HP Thin Pro". I will report the incorrect data and thus, after my own research, I think I have answered my own question.

If you do everything via the server, there doesn't necessarily have to be an OS on it:
"There is no clear definition for these thin clients. As a rule, they are understood to be desktop computers without their own mass storage (hard disk, CD drives), which can be configured and managed via central management software".

If I see it correctly, none at all. I will quote Wikipedia at this point:
"A thin client, lean client or slim client is usually a computer that is connected to a server via a network and uses its resources."