Does VR have 3D?

Could you please clarify for me if Virtual Reality, or VR, inherently possesses the capability of 3D display? I'm curious about the fundamental connection between these two concepts and whether VR technology is inherently designed to provide a fully immersive, three-dimensional experience for its users. Is it accurate to say that VR always involves 3D elements, or are there instances where VR can be experienced without this defining characteristic?