关键词：云计算；API；云服务；SaaS；云部署
摘 要：The key to proper use of the cloud by enterprise information technology (IT) organizationsdepends on the deployment and consumption of cloud-based web services such as applicationprogramming interfaces (APIs). This article explains what a Representational State Transfer(REST) API is, the structure of an API, how REST APIs interact with cloud providers'infrastructure, a sample REST API for the cloud, REST and software as a service (SaaS),REST and platform as a service (PaaS), and various use cases.