Roughly speaking, Cloud Computing is ...
- the concepts of utility computing
- the commoditisation of certain I.T. activities (through high levels of ubiquity)
- the consequent growth of volume operation specialists (the "as a Service" industry)
- the development of underlying virtualisation, cluster and grid technologies (computing resources being provided by a mesh of devices and grids as opposed to a single identifiable device.)
... combined together to cause a disruptive transition of the computing stack (application, platform and infrastructure) from a product to a service based economy.
Whilst I wholeheartedly support attempts to provide a taxonomy for various elements of cloud computing, the attempt to come up with a precise, all encompassing and concrete definition of cloud computing is flawed.
Cloud computing isn't a thing, it's a combination of underlying factors that are causing a transition in the information technology industry. We will eventually get a reasonable definition for this concept but it will be described in volumes and not a short snappy sentence. That said, I thought I'd now provide my very own short snappy definition:-
“Cloud computing” is a consequence of economic, commercial, cultural and technological conditions that have combined together to cause a disruptive shift in I.T. towards a service based economy.
I'll change my view when someone, 200 years after the event, can give me a precise, all encompassing, concrete definition of the "industrial revolution" without requiring me to read a book or watch a documentary.
Of course, I'll always welcome suggestions on good books to read.