The NodeMCU ESP8266 is a popular open-source IoT platform based on the ESP8266 Wi-Fi module from Espressif Systems. It combines a microcontroller with built-in Wi-Fi capability, making it ideal for connecting devices to the internet easily and affordably.
 
Here’s a quick overview:
Feature
Details
Microcontroller
ESP8266
Operating Voltage
3.3V (but many pins are 5V tolerant through resistors)
Flash Memory
Typically 4MB (varies by board version)
Wi-Fi
802.11 b/g/n (built-in)
Programming Language
Lua scripting language (original) or Arduino IDE (popular)
Interfaces
UART, SPI, I2C, PWM, ADC (10-bit), GPIO
USB Interface
Micro-USB for power and programming
 
Main Advantages
Low cost
Built-in Wi-Fi for easy IoT projects
Compatible with Arduino IDE (easy to code)
Small and compact
 
Common Applications
Home automation
Remote sensor monitoring (temperature, humidity, etc.)
Smart agriculture
Weather stations
Wireless data logging
IoT-based healthcare systems
 
Package includes: 1xESP8266