This tutorial is for helping you to flash firmware in your favorite ESP8266 module. First i small introduction to ESP8266:
The ESP8266 is a low-cost Wi-Fi chip with full TCP/IP stack and microcontroller capability produced by Shanghai-based Chinese manufacturer, Espressif. The chip first came to the attention of western makers in August 2014 with the ESP-01 module, made by a third-party manufacturer, AI-Thinker. This small module allows microcontrollers to connect to a Wi-Fi network and make simple TCP/IP connections using AT commands. It also has a decent amount of internal memory (512kb-4mb), so it can also be used as a standalone IoT device with lesser number of GPIO pins.
Flash Firmware To ESP8266 WiFi Module the easy way – [Link]