Quoting from the Parallels official announcement:
Parallels is making installation of the Windows operating system on a Mac even easier than installation on a PC with the introduction of the Parallels Installation Assistant. The software comes included as part of Parallels Desktop for Mac…
The Installation Assistant provides a powerful, easy to use ?Express Windows OS Installation Mode? for Windows XP and Windows Vista that completely automates the virtual machine setup and Windows installation processes. Users select which Windows version they plan to use, enter their name, company information and Windows activation key, and then click ?finish? to begin installing Windows in a pre-designed virtual machine that has been optimized for their version of Windows. From that point on, installation is completely automated and requires no user interaction; users do not need to enter any additional information, select settings, or answer any potentially confusing technical questions posed by Windows during installation.
After Windows installation is complete, the Installation Assistant automatically installs Parallels Tools, a free set of useful add-ons that improve networking, video, and sound support, syncs mouse activity and OS system clocks, and enables cutting, copying and pasting of data, as well as and file sharing, between Windows and OS X.
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In addition to the Installation Assistant, the new build of Parallels Desktop for Mac offers Shared Networking, a powerful new networking mode that lets users seamlessly connect their virtual machines to the internet via a cable modem, LAN, broadband card, Wi-Fi connection, or dial-up modem, without any manual network reconfiguration. Because Shared Networking enables multiple IP addresses to appear as one IP address on a network, it enables users working with internet connections like DSL or Cable modems that are only configured for use with a single IP address to easily connect their virtual machines to the internet. This same feature also effectively hides virtual machines from the outside world, making them far less likely to be the victim of a hacker attack.
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Existing Parallels Desktop for Mac users with auto-update enabled will receive the Installation Assistant and Shared Networking feature automatically…