Simply explained (too simple maybe): a hard disk can have 0 (it's unusable then!), 1 or more partitions. Each partition becomes a drive-letter in Windows.
Fdisk is a (limited) partition manager, used to delete and create partitions.
Once you have a c:, you only need to format it. Which is: delete everything that's on it and initialize it to a state ready to receive files.
I assume you know what to do before you format the disk and how to proceed thereafter. A quick overview I wrote a few days ago: http://reviews.cnet.com/5208-6618-0.html?forumID=6&threadID=17136&messageID=188641.
When it doubt: post for advice or helpful links.
Hope this helps.
Kees
I want to clean my hard drive (only have one) and then reinstall windows, but I'm confused as to whether I should fdisk or format it. I appreciate any help.
Thanks.

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