BIOS uses the Master Boot Record (MBR) and UEFI uses the GUID Partition Table (GPT). As such, BIOS saves all its information on a BIOS chip on the motherboard and UEFI saves its data to an EFI ...
Several IBVs (Independent Bios Vendors) offer their implementations of UEFI that OEMs who produce motherboards can license and use in their products. Some examples would be AMI, Phoenix ...