Application virtualization is different than machine virtualization which virtualizes the machine on which an operating system (and applications) are installed. Machine virtualization provides an abstraction layer between the hardware and the OS that's running on top of it. It also allows managing and simultaneously operating multiple environments on a single machine.
Application virtualization takes this concept and applies it to programs. The abstraction layer created by application virtualization lies between the operating system and the applications that run within it, allowing applications to be delivered dynamically
as services that can be added or removed without installation.
Microsoft purchased a company named Softricity a while ago and the application virtualization product SoftGrid was forged from the algorithms created by both Softricity and Microsoft engineers.
"Microsoft SoftGrid Application Virtualization provides the most extensive virtualization on the market. In addition to virtualizing application related Windows Services, it virtualizes per user, per application instance, key application components including the Registry, file system, DLLs, COM/IPC, .INI files, fonts and more.
SoftGrid's application virtualization can work in concert with other virtualization technologies – including machine virtualization – as part of a comprehensive services-oriented architecture."
Here, John Sheehan, the primary architect of SoftGrid (formerly the chief architect of Softricity) digs into the details of how application virtualization (as implemented in SoftGrid) works. It's an incredibly interesting technology with a very promising future. There are many possibilities for using application virtualization to solve problems affecting not only the enterprise, but standard users and developers as well. Just use your imagination. This is a deep dive and John told me he'd like to go even deeper next time he's in Redmond. For now, this conversation should suffice as a technical introduction to the world of application virtualization and how Microsoft is innovating in this space.