Cloud Computing: What Is It & Why Should I Care?

Cloud computing represents a shift from mainframe to client–server environments to a delivery model for IT services based on the Internet.

 Shared resources, software and information are provided to computers and other devices on-demand, providing businesses the benefits of anywhere, anytime access to data, improved reliability, and software that is up to date with less of a potential of malware (relative to laptop storage).

Source : http://wikibon.org