Released on June 15, 2006, it was the first software product to bring virtualization mainstream to Macintosh computers utilizing the Apple–Intel architecture (earlier software products ran PC software in an emulated environment).
Its name initially was 'Parallels Workstation for Mac OS X', which was consistent with the company's corresponding Linux and Windows products. This name was not well received within the Mac community, where some felt that the name, particularly the term “workstation,” evoked the aesthetics of a Windows product. Parallels agreed: “Since we've got a great Mac product, we should make it look and sound like a Mac product...”, it was therefore renamed ‘Parallels Desktop for Mac’.
On January 10, 2007, Parallels Desktop 3.0 for Mac was awarded “Best in Show” at MacWorld 2007.
Parallels Desktop for Mac is a hardware emulation virtualization software, using hypervisor technology that works by mapping the host computer’s hardware resources directly to the virtual machine’s resources. Each virtual machine thus operates identically to a standalone computer, with virtually all the resources of a physical computer. Because all guest virtual machines use the same hardware drivers irrespective of the actual hardware on the host computer, virtual machine instances are highly portable between computers. For example, a running virtual machine can be stopped, copied to another physical computer, and restarted.
Parallels Desktop for Mac is able to virtualize a full set of standard PC hardware, including
A virtualized CPU of the same type as the host's physical processor,
A 1.44 MB floppy drive, which can be mapped to a physical drive or to an image file,
Up to four IDE devices. This includes virtual hard drives ranging in size from 20 MB to 2 TB each and CD/DVD-ROM drives. Virtual CD/DVD-ROM drives can be mapped to either physical drives or ISO image files.
DVD/CD-ROM “pass-through” access,
Up to four serial ports that can be mapped to a pipe or to an output file,
Up to three bi-directional parallel ports, each of which can be mapped to a real port, to a real printer, or to an output file,
The first official release of version 2.5 was on February 27, 2007, as build 3186.
Version 2.5 brought support for USB 2.0 devices, which expanded the number of USB devices supported at native speed, including support for built in iSight USB web-cams. The amount of video RAM allocated to the guest OS was made adjustable, up to 32MB. Full featured CD/DVD drives arrived in this version, which allowed the user to burn disks directly in the virtual environment, and play any copy-protected CD or DVD as one would in Mac OS X. In addition, a shared clipboard and drag-drop support between Mac OS X and the guest OS was implemented. This version brought the ability for users with a Windows XP installation to upgrade to Windows Vista from within the VM environment. A new feature known as Coherence was added, which removed the Windows chrome, desktop, and the virtualization frames to create a more seamless desktop environment between Windows and Mac OS X applications. This version also allowed users to boot their existing Boot Camp Windows XP partitions, which eliminated the need to have multiple Windows installations on their Mac. A tool called Parallels Transporter was included to allow users to migrate their Windows PC, or existing VMware or Virtual PC VMs to Parallels Desktop for Mac.
In 2007, the German company Netsys GmbH sued Parallels' German distributor Avanquest for copyright violation, claiming that Parallels Desktop and Parallels Workstation are directly based on a line of products called “twoOStwo” that Parallels developed on paid commission for Netsys, of which it says, Netsys has been assigned all copyrights. Additionally, the lawsuit claimed that Parallels Desktop 2.5's compatibility with “twoOStwo” showed that the two software products are run by essentially the same functional core. When Netsys lost its initial urgency proceeding, in which it requested a temporary injunction from the Landgericht district court of Berlin, it filed a new suit.
On June 7, 2007 build 4124 was released as the first publicly available version of Desktop 3.0.
Version 3.0 retained all of the functionality from previous versions and added new features and tools. Support for DirectX 8.1 and OpenGL was added, allowing Mac users to play some Windows games without the need to boot into Windows with Boot Camp. A new feature called SmartSelect offers cross OS file and application integration by allowing the user to open Windows files with Mac OS X programs and vice versa. Parallels Explorer was introduced, which allows the user to browse their Windows system files in Mac OS X without actually launching Windows. A new snapshot feature was included, allowing one to restore their virtual machine environment to a previous state in case of issues. Further, Parallels added a security manager to limit the amount of interaction between the Windows and Mac OS X installations. This version included a long awaited complete “Parallels tools'” driver suite for Linux guest operating systems. Therefore integration between Mac OS X and Linux guest-OS's has been greatly improved.
Despite the addition of numerous new features, tools and added functionality, the first iteration of Desktop for Mac 3.0 may be missing some of features that Parallels had planned for it. A Parallels, Inc. representative stated at MacWorld in January 2007 that version 3.0 would bring accelerated graphics, “multi-core virtual machines/virtual SMP, some SCSI support, a more Mac-like feel, as well as a more sophisticated coherence mode, dubbed Coherence 2.0”. While accelerated graphics have materialised, Coherence, as well as the overall look and feel of Parallels Desktop for Mac has only changed slightly. Also, SCSI support has not been implemented.
It is currently unknown if these features have been abandoned altogether, or if they will show up in a later build of version 3.0.
Build 4560, released on July 17, 2007, added an imaging tool which allowed users to add capacity to their virtual disks.
Parallels Coherence in Exposé
Build 5160, released on September 11, 2007, added some new features and updated some current features.
The release focused on updates to Coherence, with support for Exposé, window shadows, transparent windows, and the ability to overlap several Windows and Mac windows. Further, Parallels' Image Tool was updated to allow one to change their virtual hard disk format between plain and expanding. Parallels Explorer was updated to allow for one to automatically mount an offline VM hard drive to the Mac desktop. Some new features added are iPhone support in Windows, allowing iTunes in Windows to sync with it. Users can now mirror desktops or other folders. Further, Mac drives can now be mapped by Windows and sound devices can now be changed ‘on the fly’. Up to 2 GB of RAM can be allocated to a virtual machine, with a total of 4 GB of RAM available.
Parallels Desktop for Mac Build 5608 added support for guest Parallels Tools for Linux in the latest Linux distributions (including Ubuntu 8). It also added support for running 3D graphics in Windows virtual machines on Mac OS X Leopard 10.5.3.
Use of code from the Wine project
According to Parallels' Licensing page, Desktop for Mac version 3.0 contains Direct3D code that was originally developed by the Wineopen source project. Wine software is licensed under the GNU Lesser General Public License, which required Parallels to release the source code. Parallels released the modified source code on July 2, 2007, about 2 weeks after the promised release date. A Parallels spokesman explained the reasons for the delay in a message on the official company blog.
Version 4.0, released November 11, 2008, updates its GUI, adds some new features, enhances its performance by up to 50% and has been developed to consume 15–30% less power than previous versions. Version 4.0 is the first version of Parallels Desktop that supports both 32-bit and 64-bit guest operating systems. Parallels Desktop 4.0 for Mac’s 3D support includes DirectX 9.0, DirectX Pixel Shader 2.0 and OpenGL 2.0  as well as 256 MB video memory. It also adds support for 8 GB RAM in a virtual machine and 8-way SMP. Parallels Desktop 4.0 introduces an adaptive hypervisor, which allows users to focus the host computer’s resources towards either host or the guest operating system.
Parallels Desktop 4.0 for Mac adds some new features such as:
A fourth viewing mode called Modality, which allows users to scale the size of an active guest operating system on the Mac’s desktop
A new screenshot utility called Clips, which lets users take and share screenshots between the host and the guest operating systems.
Start Menu integration and Automatic Windows Notifications on the Apple Menu Bar.
The ability to use select voice commands to remotely control the virtual machine.
The ability to start and stop a virtual machine via the iPhone. (Requires installing an iPhone application from Apple's AppStore.)
Since the Version 4.0 release, Parallels Desktop for Mac has a new logo. The new logo has what resembles an aluminum iMac, with what appears to be Windows XP on the screen and 2 parallel red lines overlaid on right side.
Build 3810, released January 9, 2009, includes performance enhancements and features, such as DirectX 9.0 Shaders Model 2 and Vertex Shader support for additional 3D support Intel Streaming SIMD Extensions (SSE4) for better media applications performance. Build 3810 also adds support for running Windows 7 in a VM and for running Mac OS X Snow Leopard Server as either a host or as a guest OS.
Also included are usability features such as the ability to share Windows files by dragging them directly to a Mac application in Mac Dock. Windows can now also automatically start in the background when a user opens a Windows application on the Mac desktop. Version 4.0 drew criticism for problems upgrading from Version 3.0 shortly after its initial release. Build 3810 also addresses installation and upgrade issues previously experienced with Version 4.0 and introduces the option to enroll in the company's new Customer Experience Program, which lets customers provide information about their preferences and user priorities.
Officially released on November 4, 2009, Parallels Desktop 5 adds several new features, mainly to improve integration with the host OS.
New features include:
3D graphics and speed improvements
Optimized for Mac OS X 10.6 (Snow Leopard)
Support for Windows 7
Theming of Windows applications to make them look like native applications
Support for Multi-Touch gestures (from a trackpad or Magic Mouse) and the Apple Remote
The ability to drag and drop formatted text and images between Windows, Linux, and Mac applications,
The ability for a system administrator to lock down a virtual machine so that users can't change the state of the virtual machine,
Support for OpenGL 2.1 for Linux guest virtual machines.
support for DirectX 9c with Shader Model 3.
Build 9308, released on December 21, 2009, added some new features.
Linux guest operating systems
Parallels Tools support Xorg 1.7 in Fedora 12 virtual machines (experimental)
Parallels Tools support Mandriva 2010 (experimental)
Improved resume from suspend in virtual machines with multiple monitors assigned.
Improved performance of file access via Shared Folders.
3D and video
Improved performance for video playback in Windows Vista and Windows 7.
Windows Aero is not available by default for machines with Intel GMA X3100 and GMA 950 graphic adapters (some MacBook and Mac Mini models). It is available on MacBooks with NVIDIA 9400M graphics cards.
Vertical synchronization is now configurable. You can configure these settings using the corresponding option in the virtual machine video configuration page.
The ability to pass kernel options to the Mac OS X Server guest OS has been added. To do so, enable the "Select boot device on startup" option in the virtual machine configuration: it will enable you to specify the necessary kernel options in the 5-seconds timeout before booting the kernel.
Officially announced on September 9, 2010 and launched on September 14, 2010, Parallel 6 supports full 64-bit support for the first time. Parallels claims that Parallels Desktop 6 for Mac "[has] over 80 new and improved features, including speed 40% above the previous version." Specific new features include:
An all-new 64-bit engine
5.1 Surround Sound support
Better import implementation of VMware, Virtual PC virtual machines and Boot Camp partitions
Improved network, hard drive and Transporter performance
Windows program Spotlight integration
Faster Windows launch time
Enhanced 3D graphics that are 40% better than previous versions
Ability to extend Mac OS X Parental Controls to Windows applications
Ability to use Mac OS X keyboard shortcuts in Windows applications
Enhanced Spaces and Exposé support
Officially announced on September 1, 2011 and released on September 6, 2011, Parallels Desktop 7 adds many new features, compared to its previous version.
The list below contains most important features (according to developer's website) but is not exhaustive:
Integration with Mac OS X Lion :
Use of Launchpad for Windows apps
Mission Control support
Lion as a guest OS
Lion animations support
Improved user interface
New standard help and documentation
Shared devices with Mac OS X
Longer battery life
Mac OS X parental controls support
Support for Intel AES-NI encryption
Enhanced performance and 3D graphics
Support for up to 1GB video memory in virtual machine
Enhanced audio support - up to 192 kHz
Surround sound 7.1
Added support for Windows 7
Officially announced on August 22, 2012 and released on September 4, 2012, Parallels Desktop 8 adds many new features, compared to its previous version.
Mountain Lion as a guest OS
Retina resolution can be passed to virtual machines
Windows 7 and Windows 8 automatically optimised for best experience on Retina
Parallels Desktop notifications
Notification Center support for Windows 8 toast notifications
Mountain Lion Dictation in Windows apps
Full screen on demand for Windows applications in Coherence
Open in Internet Explorer button for Safari
Drag & drop file to Outlook in the Dock opens new email with attachment
Multi-language Keyboard Sync in Mac and Windows
Full support for new Modern UI Windows 8 applications (Dock, Mission Control, Launchpad)
Reworked Keyboard shortcuts preferences
Use the standard OS X system preferences to set Parallels Desktop application shortcuts.
Resources (CPU/RAM) monitoring
Indication for VM hard drive space usage
Improved Virtual Machine boot time/Windows boots time are up to 25% faster than previous version
Pause & resume Windows up to 25% faster than previous version
Input/output (I/O) operations are up to 35% faster than previous version
Games run up to 30% faster than previous version
DirectX 10 support
Full USB 3.0 support for faster connections to peripheral devices for Virtual Machines starting from Parallels Desktop 8.0.18305 (see http://kb.parallels.com/en/115008)
Officially announced on August 29, 2013 and released on September 5, 2013, Parallels Desktop 9 for Mac adds includes these new features and enhancements over previous versions:
Brings back the "real" Start menu for Windows 8 and enables Modern apps in separate windows instead of full screen
Power Nap support, so applications stay up-to-date on Retina Display Mac and MacBook Air computers
Thunderbolt and Firewire storage devices are designated to connect to Windows virtual machine
Sticky Multi-monitor setup remembers settings and puts Windows virtual machines back into Full Screen mode on the remote monitor
Sync iCloud, SkyDrive, Dropbox and more without unnecessary duplication of files
Windows apps can launch the OS X Mountain Lion Dictionary with Dictionary gesture
Enhanced integration with Mac OS for Linux users
Enhanced New Virtual Machine Wizard makes it easier to set up a new virtual machine, especially on computers without hard drives
PDF printer for Windows to print from any Windows application to a PDF on the Mac desktop, even if that application doesn't have that functionality
Will work with OS X Mavericks
Easily install and access complimentary security software subscriptions from one location
Up to 40% better disk performance than the previous version
Virtual machines shut down up to 25% faster and suspend up to 20% faster than with Parallels Desktop 8
3D graphics and web browsing are 15% faster than in Parallels Desktop 8
Set an expiration date to the virtual machine.
Run virtual machines in headless mode .
Start virtual machines on Mac boot.
Released August 20, 2014. Support for OS X 10.10 (Yosemite)
Supported operating systems
Parallels Desktop 9 for Mac requires a Mac with one of these processors:
In Parallels Desktop 8 for Mac, support for guest operating systems includes a variety of 32-bit and 64-bit x86 operating systems, including:
multiple versions of Microsoft Windows, including Windows 8, as well as MS-DOS, and Windows 8.1. (Windows 8.1 must generally be installed from a DVD version of Windows 8.1, since, Microsoft offers only the ".exe" version of Windows 8.1 in downloadable form, and does not offer the ".iso" version as a download.),