A typical example of a local public good is information because it reduces a costly investigation involved in the research of what is being studied. Now the information travel so fast because the social network like Facebook, Twitter, Instagram, Snapchat, etc. are changing our environment. Instead of incurring in the cost of buying a newspaper, for example, if a group of scientists create a new vaccine for cancer we can eliminate that costs and see the notice through the social media and tell our friends whats going on. That is we can think as the faster information that provide us the internet it could be treated as a positive externality because getting informed about it will incentive people to get the vaccine and the cancer diseases will drop off. Hence, it´s important to recognize that the information flows faster than 20 years ago. Now everybody can be benefited from this situation because the groups realize even faster.