The NodeMCU ESP8266 development board puts a Wi-Fi-enabled microcontroller in your hand for under ₹300. Based on the ESP-12E module, it includes a CP2102 USB-UART chip for easy programming, and runs the Lua-based NodeMCU firmware (or can be reflashed to Arduino, MicroPython, or ESP-IDF). With 11 GPIO pins, an ADC, integrated Wi-Fi stack, and only one size larger than a two-rupee coin, it's ideal for projects like weather stations, smart switches, cloud-logged sensors, and simple IoT home automation.