GitHub is where people build software. Note that this is a reference documentation and not a tutorial with fancy screen shots. Turn to your favorite search engine for those.
Make sure you follow a recent tutorial rather than one that is several months old! They might not want to setup a Linux VM with the build environment. The firmware uses Lua scripting language and is based on eLua project built upon ESpressif Non-OS SDK.
To prepare it for firmware flashing, GPIO should be connected to ground before you apply power to the ESP. Navigate to Github to download the firmware. You can download the actual firmware binaries in pre_built. Power your developement in the fastest way combinating with NodeMcu Firmware ! USB-TTL include plugplay. GPIO, every GPIO can be PWM, I2C, 1-wire.
FCC CERTIFIED WI-FI module, PCB antenna. A few examples to play with. Open terminal and go to the folder where you have esptool. You simply wire your circuit, download the flasher and hit flash.
NodeMCU is an open source IoT platform. Where communities thrive. Explore more communities. Browser, Desktop and Mobile Apps. Download nodemcu - firmware from Bintray.
They just need a ready-made firmware. I created a cloud build service with a nice UI and configuration options for them. To use on the first time, NO need to flash the firmware, run command file.