What is VMWare Fusion? How does VMWare Fusion compare to Parallels Desktop for Mac?

First announced on August 7, 2006, released in a limited beta version on or around November 3, 2006, released as a public beta on December 21, 2006, and shipped as a "final" product on August 6, 2007, Fusion is VMWare's virtualization solution that allows one to run other operating systems "inside" or "alongside" MacOS X. In much the same way as Parallels Desktop for Mac, VMWare states that Fusion provides:

The ability to simultaneously run any PC OS -- Windows, Linux, NetWare and others -- on Mac OS X. Switch between operating systems by easily tabbing between applications and share data between the two operating systems by dragging and dropping files on the fly -- all without needing to reboot. What's more, you can create virtual machines and run them on other VMware products or run any VMware virtual machine on your Mac.

TUAW published a leaked memo regarding the features of VMWare Fusion on November 3, 2006. Of these features, most were already provided by the shipping Parallels Desktop for Mac, but of particular interest to many, VMWare also promised the following:

• The ability to assign more than one processor, or more than one processor core (when available), to the program to improve performance.
• Access to physical devices from within VMWare, such as "CD-ROM drives, video cameras, iPods, printers, and high-speed disks".
• Support for USB 2.0 devices.
• The ability to drag and drop files between MacOS X and the guest operating system running within VMWare Fusion.

When the public beta was released VMWare listed the same features officially on the company website.

On November 29, 2006, when this Q&A was first published, EveryMac.com noted that Parallels Desktop for Mac used a single core on a dual core Mac, did not provide direct access to the physical CD/DVD-ROM drive, did not provide support for devices that require USB 2.0, and required users to share files using Parallels Tools, which is convenient, but not quite as convenient as drag and drop.

However, EveryMac.com also remarked that it was a safe bet that the programmers at Parallels were hard at work adding most, if not all, of the features that VMWare promises to the next release of Desktop for Mac. Sure enough, two days later, Parallels unveiled beta build 3036, with the ability to "drag and drop" files between MacOS X and Windows, the ability to boot from a Boot Camp partition, a slick "coherency" feature to "show Windows applications as if they were Mac ones", improved graphics performance, and a slew of other improvements.

On December 21, 2006, Parallels released another beta that added support for many USB 2.0 devices, CD burning, and Boot Camp partition support, and a few days after that (December 29, 2006), released "Beta 3" (Build 3106) with better Boot Camp and USB 2.0 support, an improved version of Transporter that made it possible to "migrate your real Windows PC, or existing VMware or Virtual PC VMs to Parallels virtual machines", a new interface, and more.

When this Q&A was "archived" on August 16, 2008, VMWare Fusion notably supported the ability to assign more than one processor or core to an application and Parallels Desktop for Mac did not, with the next version promised to do so, but otherwise both products are similar, high-quality and do the job of running Windows "alongside" MacOS X admirably.

In a wonderfully in-depth comparison that should be read in its entirety, the always excellent MacTech found:

If you want a virtualization product (that allows you to run Windows alongside Mac OS X), and you want the best performance for the types of things that we tested, then clearly you need to run XP and not Vista. Furthermore, in our tests, both VMware Fusion and Parallels performed well, and were a good user experience. That said, Parallels was somewhat faster in general than VMware Fusion for XP.

If you want the best virtualization performance for Vista, then VMware Fusion is your choice. And, if you want to keep your Mac OS X and Windows environments completely separate, VMware Fusion's design may be your better choice (And, although we didn't test it, we would expect VMware Fusion to have better multi-processor support if you really have an application that is designed to take advantage of it [other tests confirm this]). If your goal is tight integration between one or more Windows applications and Mac OS X, Parallels is the clear winner when running either XP or Vista. And, as we said before, if you want the best XP performance with the types of applications tested here, Parallels is not only faster than VMware Fusion, but it's faster than Boot Camp on average for the applications that we tested.

Ultimately, Parallels Desktop for Mac and VMWare Fusion will continue to be improved at a rapid rate and each is available to download to try for free and you can decide which program you prefer. Amazon.com offers both Parallels Desktop for Mac and VMWare Fusion at a discount compared to purchasing direct from either company.