OS says Windows NT; I have Windows XP

While following instructions to remove unused device drivers from “Environment Variables” in my Windows XP Home system, I noticed under “System variables” that my OS states “Windows_NT.” I am using Windows XP Home. Is it okay that it says NT and not XP? If it should indicate XP, will you kindly instruct me as to how to correctly edit it, i.e., should it state “Windows_XP”? Thank you in advance.