This document provides an introduction to the Internet of Things (IoT). It defines IoT as connecting various "things" through networks to enable those things to communicate. The document outlines key enabling technologies for IoT like RFID, wireless networks, and sensor networks. It also describes the layered architecture of IoT including sensing/communication layers, middleware, and applications. Middleware is highlighted as an important software layer that processes data from networking layers and provides solutions for issues like heterogeneity and interoperability in IoT.