What means to be a root device on EC2?

Question

I couldn\'t find the answer on EC2 documentation. What is it for? If I launched an EBS backed instance, the root device for the instance would be an EBS volume. If I install

Answer 1

This may have been added since you asked, but I believe this answers the question:

http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/RootDeviceStorage.html