Comment by hapless

Arguably it had a great deal to do with what we think of as a "virtual machine."

Virtual 8086 remapped all opcodes and memory accesses to let a program pretend to be on a single, real-mode 8086 when in reality it was one of many programs running in protected mode on a newer chip

AMD-V and whatever the Intel counterpart is do the almost exactly the same thing: re-map all ia32 and amd64 instructions and memory accesses to let a program pretend to be doing ring 0 stuff on an x86 box, when in reality it is one of many programs running with fewer privileges on a newer chip

There are a few more wrinkles in the latter case -- nested page tables, TLB, etc -- but it is the same idea from the viewpoint of the guest.