Clearing up Cloud Confusion

Cloud computing. Utility computing. SaaS. Software + Services.
What does it all mean?

Here's a quick primer on what these terms mean and how they are related.

Web 2.0
The second-generation uses of the web, which emphasize social networking, collaboration, and sharing.
Examples: Facebook, MySpace, Flickr, blogs, communities

Software as a Service (Saas)
Software you access over the Internet to use.
Examples: SalesForce.com, NetSuite, Taleo, RightNow.

Utility Computing
Charge for use of hosted computing resources.
Pay-as-you-go based on what you use, just like electricity or water from a utility.

Software + Services
Microsoft's term for some software local ("Software") and some software out in the cloud ("Services").
Example: iTunes.

Cloud Computing
Internet-based development - platform is a data center.
Run your own software in the cloud with fantastic ability to scale.