Partitioned storage [From windows] to use as regular storage?

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http://askubuntu.com – Maybe it's a new user question, but coming from Windows 8 I was asked to partition my hard drive to install Ubuntu. How can I use that extra space as I once did in Windows? As one big Hard Drive, instead of two different storage locations? I would hope I don't have to delete any files, as I still want to use Windows as well. (HowTos)