A virtual world can be infinitely large. In contrast, the physical space in which you can move is limited to a few square meters. As a result, it’s not possible to traverse the entire virtual world by walking. You would inevitably encounter the real boundaries.
That’s where “locomotion” comes in. It’s a way to move around in the virtual world while staying in the same physical position.
The most common method is teleporting. You point to a spot with a virtual ray and instantly move to the new position.