Partition 1 - Recovery
Partition 2 - System - The EFI System partition that contains the NTLDR, HAL, Boot.txt, and other files that are needed to boot the system, such as drivers.
Partition 3 - MSR - The Microsoft Reserved (MSR) partition that reserves space on each disk drive for subsequent use by operating system software.
Partition 4 - Primary - Where Windows is to be installed to.