Cloud computing is a model for delivering information technology services over the Internet. It allows users to access and use shared resources, such as servers, storage, and software, over the Internet on a pay-as-you-go basis. This eliminates the need for organizations to invest in and maintain their own IT infrastructure and resources.

The cloud computing model has several different service models, including Infrastructure as a Service (IaaS), Platform as a Service (PaaS), and Software as a Service (SaaS). IaaS providers such as Amazon Web Services and Microsoft Azure offer virtualized computing resources such as servers, storage, and networking. PaaS providers such as Heroku and Google App Engine, offer a platform for developing, running, and scaling applications. SaaS providers such as Salesforce and Microsoft Office 365, provide users with access to software applications and services over the Internet.