ESP8266 is an economic(Low-cost) open-source IoT Platform having micro-controller capability.
ESP8266 NodeMCU is also called Single Board Micro-Controller. It has 128 KBytes Memory and 4 MBytes of Storage.
ESP8266 NodeMCU’s firmware and prototyping board were open-source which means anyone could modify it and make it his or her own.
ESP8266 WiFi firmware was written in Lua Scripting Language and it supports MQTT IoT Protocol.
Now, we can program ESP8266 NodeMCU using Arduino IDE because Some ESP8266 Enthusiasts developed an Arduino Core for ESP8266 WiFi SoC.
Let’s try to do some practical example with ESP8266 WiFi