The project, created by the same Google X team who made self-driving cars and Google Glass, aims to bring internet to the two-thirds of the global population currently without web access.
See more :
http://www.telegraph.co.uk/technology/google/10120198/Googles-internet-balloons-offer-remote-areas-web-access.html
http://googleblog.blogspot.be/2013/06/introducing-project-loon.html