The "Cloud" is a series of huge, (5 or 6 buildings) server complexes where
all internet content is being moved to.
For example, Windows Live is hosted on the Cloud.
Windows Live replaced all of the Windows media programs such as
Movie Maker and Media Player which used to be standard programs
included with Windows on all new pcs.
The last I read, there 4 - 6 of these complexes around the world.
1 in Mexico, 2 in the U.S. and, I believe, 2 or 3 in Europe.
And they're building more on an ongoing basis.
Now major corporations are moving all their IT info out of house and into the Cloud.
This includes banks and hospitals.
GPS tracking systems in cars so "they" can track you wherever you go.
Google Earth so "they" can see you wherever you are.