Contiki is an open-source operating system designed for the Internet of Things (IoT). It is lightweight and optimized for low-power devices, making it suitable for applications like smart sensors and home automation. Contiki supports various communication protocols, enabling devices to connect and share data efficiently. The operating system features a unique event-driven programming model, which helps manage resources effectively. It also includes a built-in network stack that supports IPv6, allowing devices to communicate over the internet. With its modular architecture, developers can easily customize and extend Contiki for specific IoT applications.