If you want to run PC software on the Mac and use Parallels software to do
so, then you will need
-- Parallels software installed on the Mac
-- An operating system - Microsoft Windows whatever (or even Linux if you
wish)
-- Whatever PC software you want to run
So, yes you will need to purchase an operating system.
Presently I am running Windows XP on my Mac computer, along with Microsoft
Office 2003 and other PC software.
As for how to install all this, you wil need to read the instructions that
come with the software and follow the procedures.
--
John Spencer
Access MVP 2002-2005, 2007-2008
Center for Health Program Development and Management
University of Maryland Baltimore County
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