Why does my HDD have weird partitions?

Solution
There you have it - 499MB Recovery partition and 99MB bootloader partition. Recovery partition is necessary for recovery mode, bootloader partition is necessary for booting up your pc. No need to touch those.
If it's in a laptop or a factory-built PC it's quite normal - - - as well as the user partition (C) there'll be a factory recovery partition containing a backup image of the OS, and a boot manager partition.

Those two partitions are usually hidden (no drive letter assigned to them) for safety & security reasons, so you don't see them except in the defragmenter utility and in Disk Management.
 


It's my own build, I just finished it yesterday.