The ESP8266 is a low-cost, Wi-Fi-enabled microchip with a full TCP/IP stack, widely used in IoT (Internet of Things) applications. It allows devices to connect to the internet and communicate wirelessly, making it ideal for smart home projects, sensors, and remote control systems. The chip includes a microcontroller with sufficient processing power for many applications and can be programmed using the Arduino IDE or other platforms. Its compact size, low power consumption, and versatility have made the ESP8266 one of the most popular Wi-Fi solutions for hobbyists and developers working with connected devices.