New installation of Bootcamp and Windows 7 over Parallels - What is the D Drive?

Hello, I've tried searching for this but couldn't find any answers... I just finished installing a new copy of Windows 7 under bootcamp and then used parallels to access bootcamp. Now when I click on my computer in windows 7 while in parallels, there is a C drive, my shared folders, and then there is a D drive.

When I try to double click on the D drive windows says that the disk needs to be formatted. When I right click to see properties it shows as 0 megabytes. What is this D drive? I don't remember setting up any additonal partitions. Is this the recovery drive on my mac or something else?

Also I should note that I do have mac drive installed on my windows 7 partition (I thought the D drive was my OSX partition at first but that doesn't appear to be the case). Anyway, some insight as to what this is would be helpful!

I am hesitant to click on format as I don't know what the drive is!

Thanks!