The NodeMCU IoT board is a popular open-source development board built around the ESP8266 Wi-Fi module, designed specifically for Internet of Things (IoT) applications. It comes with a built-in microcontroller and Wi-Fi connectivity, allowing devices to connect directly to the internet without needing an external network processor. The board can be programmed using the Arduino IDE or Lua scripting language, making it very beginner-friendly as well as suitable for advanced IoT developers. NodeMCU provides several GPIO (General Purpose Input/Output) pins, analog input, PWM outputs, I²C, SPI, and UART communication protocols, making it versatile for interfacing with sensors, actuators, and other electronic components. It typically operates at 3.3V logic and is powered either via a micro-USB cable or an external power supply. With built-in flash memory and a 32-bit processor, it is capable of handling multiple IoT tasks efficiently. Because of its low cost, compact size, and integrated Wi-Fi, the NodeMCU board is widely used in home automation, smart devices, wireless sensor networks, and cloud-based IoT projects. Its large online community support and ease of use make it one of the most popular boards for IoT prototyping and learning.