This document provides an overview of Internet of Things (IoT) and Industrial Internet of Things (IIoT). It discusses key concepts including sensors, gateways, connectivity protocols, cloud platforms, security, and applications. Specifically, it describes how sensors collect data and transmit it via protocols like MQTT and AMQP to gateways, which perform edge analytics and send data to the cloud for storage and processing using services like AWS IoT. The cloud platform then makes this data available to applications and end users.