Cloud computing

Cloud computing delivers computing services (software, servers, databases, storage and more) over the Internet. You can use them from anywhere, on any device. They are provided by cloud service providers, usually on a pay per use basis, the way we pay for electricity: you pay for what you use.

The great advantage: a user can run big applications or process huge amounts of data without owning expensive hardware. Resources are available on demand, and are cost-effective.

Cloud services come in three models:

• Infrastructure as a Service (IaaS): the provider supplies the basic infrastructure: servers, virtual machines, storage, backup, networks and operating systems. The user can run any application on this remote infrastructure, and saves the cost of setting up and maintaining it.
• Platform as a Service (PaaS): the provider supplies a ready platform to develop, test and run applications, such as a server already set up with a web server program, a database (MySQL) and a programming language (Python). The user just builds the application.
• Software as a Service (SaaS): the provider supplies ready application software, used on demand through a browser, often by subscription: Google Docs, Office 365, Dropbox.

The Government of India has its own cloud, the GI Cloud, called 'MeghRaj'.