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Any one will do, but you may have to format it first if it comes pre-formatted in NTFS. (Not sure if hard drives come pre-formatted at all, come to think of it)
 
Like TPAM said, all harddrives are the same until your format them :)

Macs can read FAT32, HFS+ and NTFS. They cannot write to NTFS, however.
Windows can read/write FAT32 and NTFS, but not HFS.

So if you intend to share this with a Windows PC, I recommend formatting as FAT32. If it'll ONLY be used with your Mac, I'd go with HFS+ (because...well, why not?)
 
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