That makes sense thanks.Split a single slot into many, in its most basic sense.
As an example, a GPU would use a single X16 or X8 lanes from a wired X16 PCIe slot. When you use bifurcation, you can turn that same slot into an X8/X8 or X4/X4/X4/X4. This is normally found with storage devices and some GPUs that have M.2 slots on them.