It is an emerging computing technology. Herewith the use of Internet and central remote servers to maintain data and applications. Example for this is Email service, Oce Software (word processor, spreadsheets, presentations, database, etc), graphics software, etc. The information is placed in a central remote server just like clouds in the sky hence the name cloud computing.
Cloud service models (3 major services):
1. Software as a Service(SaaS) A SaaS provider company provides more services on demand such as they allow to access both resources and applications.
Examples are Google Docs, Adobe creative cloud, Microsoft Office 365, Facebook.com, etc.
2. Platform as a Service(PaaS) A PaaS provider company provides subscribers access to the components that they require to develop and operate applications over the Internet.
Example: LAMP platform(Linux, Apache Server, MySQL, and PHP), ASP.NET, PHP and Python, Google’s App Engine, Microsoft Azure, Force.com, etc.
3. Infrastructure as a Service(laaS) It provides basic storage devices and computing capabilities as standardized services over the network.
Example: Amazon Web Services, Joyent, AT&T, GoGrid, etc.