Public goods include knowledge, official statistics, national security, and common languages. Additionally, flood control systems, lighthouses, and street lighting are also common social goods. Collective goods that are spread all over the face of the earth may be referred to as global public goods. For instance, knowledge is well shared globally. Information about men, women and youth health awareness, environmental issues, and maintaining biodiversity is common knowledge that every individual in the society can get without necessarily preventing others access. Also, sharing and interpreting contemporary history with a cultural lexicon, particularly about protected cultural heritage sites and monuments are other sources of knowledge that the people can freely access. Popular and entertaining tourist attractions, libraries and universities are other examples of public goods.