This document provides an overview of cloud computing. It begins with Gartner's definition of cloud computing as delivering elastic IT capabilities as a service using internet technologies. The document then discusses the history of cloud computing from John McCarthy's vision in 1961 to modern cloud services from Amazon, Google, and Microsoft. It explores how cloud computing solves the scalability problem by allowing resources to rapidly scale up or down as needed. The document outlines the key cloud service models of IaaS, PaaS, and SaaS and provides examples. It also shares success stories of companies like Zynga and Netflix leveraging cloud computing. Finally, it discusses potential cost savings and benefits of cloud computing through case studies.