Setting up toolchain for ESP8266
"When the ESP8266 was first announced to the world, we were shocked that someone was able to make a cheap, accessible UART to WiFi bridge. Until we get some spectrum opened up and better hardware, this is the part you need to build an Internet of Things thing...."
At the bottom of the linked article it says...
Edit: [CNLohr] points out there’s a more preferred toolchain that most people have switched to.