This document provides an overview of cloud computing. It defines cloud computing as distributed computing over the internet that delivers computing services, such as email and data storage. The document traces the history of cloud computing concepts back to the 1950s. It describes the key components of cloud computing including clients, data centers, distributed servers, and a central server that administers the system. The document also covers cloud service models, deployment options, benefits, applications, and provides a brief history of cloud computing's evolution.