Five ways of defining cloud computing

3. "The cloud simply refers to the move from local to service on the Web. From storing files locally to storing them in secure scalable environments. From doing apps that are limited to GB spaces to now apps that have no upper boundary, from using Microsoft Office to using a Web-based office. Somewhere in 2005-2008 storage online got cheaper and more secure than storing locally or on your own server. This is the cloud. It encompasses grid computing, larger databases like Bigtable, caching, always accessible, failover, redundant, scalable, and all sorts of things. Think of it as a further move into the Internet. It also has large implications for such battles as static vs. dynamic, RDBMS vs. BigTable and flat data views. The whole structure of business that relies on IT infrastructure will change, programmers will drive the cloud and there will be lots of rich programmers at the end. It is like the move from mainframe to personal computers. Now you have a personal space in the clouds.

"It is a gimmick yes, just like Web 2.0, but there are real changes these are based on. The marketing has been made around the technological advances."

4. "Grid and Cloud are not exclusive of each other... Our customers view it this way:

"Cloud is pay for usage (i.e. you don't necessarily own the resources).

"Grid is how to schedule the work -- regardless where you run it.

"You can use a cloud without a grid, a grid without a cloud. Or you can use a grid on a cloud."

5. "I typically break up the idea of cloud computing into three camps:

"Enablers -- These are companies that enable the underlying infrastructures or the basic building blocks. These companies are typically focused on data center automation and or server virtualization (VMware/EMC, Citrix, BladeLogic, Red Hat, Intel, Sun, IBM, Enomalism, etc.).

"Providers -- (Amazon Web Services, Rackspace, Google, Microsoft). The ones with the budgets and know-how to build out global computing environments costing millions or even billions of dollars. Cloud providers typically offer their infrastructure or platform. Frequently these 'As a Service' offerings are billed & consumed on a utility basis.

"Consumers -- On the other side of the spectrum I see the 'consumers' companies that build or improve their Web applications on top of existing clouds of computing capacity without the need to invest in data centers or any physical infrastructure. Often these two groups can be one in the same such as Amazon (SQS, SDB, etc.), Google (Apps) and Salesforce (Force). But they can also be new startups that provide tools & services that sit on top of the cloud (Cloud management).

"Cloud consumers can be a fairly broad group including just about any application that is provided via a Web-based service like a Webmail, blogs, social network, etc. Cloud computing from the consumer point of view is becoming the only way you build, host, and deploy a scalable Web application."

At least we've gotten that cleared up.

Computerworld Canada is an InfoWorld affiliate.