IDC got it right. Hopefully, a major analyst firm making this distinction will help dispell some of the myths and confusion surrounding the cloud.

I've been trying recently to differentiate between cloud computing and cloud services, so I was thrilled when I read that IDC predicts cloud services not cloud computing will be a $42 billion industry by 2012. The difference is not only huge, but is critical, as well. Like I've said before (here RE: IBM and here RE: Google), there is a big difference between accessing services (e.g, applications, search engines, etc.) that run on a backend cloud and hosting your own applications on that cloud. The former is far less risky on the surface, and would seem to be far more profitbale in the near-term. Cloud computing enables cloud services.

I still agree with Nick Carr that cloud computing -- or some variation on it -- will be the future of resource delivery, but that is a ways off. Cloud computing will not be a $42 billion market in three to four years, but it will be part of that figure. After all, anyone looking to offer cloud services will need to either build a cloud or rent cloud resources to enable the capabilities expected by such services.

IDC also is right to point out the opportunities the move toward cloud service presents to traditional IT vendors. Yes, there is the option to transition their existing solutions into a cloud service model, but a more immediate possibility should be selling their wares to help ISVs, Web-based companies and wannabe cloud computing providers get their clouds up and running. This what IBM, HP and Dell are doing with their Web-scale server offerings, and is what Citrix is doing with its Citrix Cloud Center. (Even grid computing vendors are looking at this possibility, given their products' capabilities in resource management.)

The point isn't to denegrate either cloud computing or cloud services, but rather to point out that the latter exists because of the former, but is not the former. Software as a service, Web tools, e-commerce platforms, etc., are increasing efficiency and flexibility for businesses and general consumers alike, and will have transformative effects on IT. By enabling these services, as well as the ability for IT users to acquire computing as a service in and of itself, cloud computing will have an equally, if not greater, transformative effect.

The point is this: there is cloud computing, there are cloud services and there are even technologies that enable cloud computing (e.g., virtualization). They are all related but not interchangeable. By IDC's definition, cloud services will grow into a large market in the next few years; not necessarily so for cloud computing. If commentators and users start to make this differentiation, it will bring clarity to the whole cloud discussion. When we talk about cloud computing adoption, we are talking specifically about companies accessing infrastructure -- not general applications or services -- via the Internet.

Again, though, there is a causal relationship. And if cloud services continue to grow like IDC (and others) predict, then even the doubters will have to ackowledge that cloud computing, at least as a platform for these services, must have pretty bright future.