what is grbl firware?

i have Arduino UNO, CNC Shield and 3 stepper motor but some people they said i need to load grbl firmware on the Arduino board but, where is it?

where is the grbl library?

please help me!


Please don't cross post! http://forum.arduino.cc/index.php?topic=587233 I have reported this thread to the moderators.

Duplicate posts waste the time of the people helping you. I might spend 15 minutes writing a detailed answer on this thread, without knowing that someone already did the same in the other thread. This behavior is not very respectful to the people you're asking for assistance. Just because we give our time freely doesn't mean it has no value.

In the future, take some time to pick the forum section that best suits the topic of your question and then only post once to that forum section. This is basic forum etiquette, which you would already know if you had read the sticky "How to use this forum - please read." post you will find at the top of every forum section. It contains a lot of other useful information. Please read it.