This document provides an introduction to the OpenSocial API. It outlines the goals of demonstrating how to create a simple OpenSocial application on Orkut, understand the basics of the OpenSocial API, and get started with real application development. Examples are provided of a "Hello World" application and a simple application that displays a user's friend list to demonstrate basic usage of the OpenSocial API. Resources for further learning and developing more advanced applications are also referenced.