Today cloud had become a common word but still many have misconception about it. And also it is still not that much elaborate as it should be. Ask a webmaster: he will say amazon and things like that. Ask a techie he will say everything you see on web is cloud. Ask a non-techie: it bring rain.
Well our techie is right , cloud computing is a phenomenon where client and server can efficiently share information and resources. So you see a mobile ( if it is connected to web) is a cloud , net-book is a cloud. But it must be noted its not a new thing. That's why many say its just a farce.
Though truth is in between. Cloud computing had gain ground only recently but since the dawn of web we have server and client thing. But at that time people use the computing power of their own net. Now surely your mobile is not handling much of the computing which are handled by remote server. But still it is nothing new. Its just a buzzword which I can say safely refers to an old terminology but with more powerful implications.
Many people ( in fact I think very few are not using them) nowadays used webemail service providers which is also a cloud computing phenomenon. Your gmail is a cloud app but a public cloud any one can use it.
Amazon and Rackspace services where you can purchase servers by hourly is also a cloud but a public even though one as only you can use it but all are applicable for it. But Microsoft Cloud Continuum ( their private one excluding Azure one) services are private as they are utilizing the hardware of the one who want to use them inside the firewalls of organization.. At first everyone seem to think about hosting but it is not about that. It can be used for developing applications , running software otherwise you can't use because you don't have much resources to run. It includes hosting and software development both.Still it is in nascent stage. You see surely you can't buy cloud to run your 3d games but in future you will be able to.
Think you will just need a mobile to have computing power much stronger than conventional computers.
You will not have to upgrades every two year because your processor have become outdated or GPU is now not much stronger.But all this came with a catch. In one word if I define them all is freedom. You don't have any freedom. You don't have any choice. Your all data are accessible to service provider. But there's still hope for those who believe in these things for this is just the beginning.