What is cloud computing?

I was at a Burns night tonight and sombody - of the older generation - was asking me what 'cloud computing' was. I had to reply that I didn't have a clue.



Enlighten me.What is cloud computing?
Cloud computing can be as simple as using a remote computer for storing or sharing files. Something like Dropbox - http://www.dropbox.com/ - would be better than most examples because the files are also synced between the computers.

Cloud computing is much more than sharing files though.

There's something called SaaS (software as a service). Here not only the files are stored somewhere else but also the applications. Examples would be Microsoft's Web Apps - http://office.microsoft.com/en-us/web-ap鈥?/a> or Google Docs - http://docs.google.com/

There's also a bunch of APIs (application programming interface) available. These can be customizable "helper" programs that make services online more personal. Examples of those would be the ones supplied by Google - http://code.google.com/more/table/

Using these a developer, could for example, customize Google Maps for use on their own website. Far quicker than having to develop the whole application themselves.

There are downsides. Unfortunately some legitimate users found this out when Megaupload got shut down a couple of days ago. Some people were using it as a storage space for their personal files. When the website got shut down so did access to their files and for some people these weren't just backups, but their sole copy.

For companies that rely solely on SaaS, and there are some, they will be in serious trouble if the provider quits, changes the apps in some way or even if internet access is cut for some reason, like some dingbat with a bulldozer cuts up a fiber optic cable for example.

Cloud computing, although a nice new name, isn't a new concept and dates from the very early days of computing when mainframe time was rented by the minute and people used dumb terminals to access the programs and files.