They are primarily responsible for maintaining and changing posture, locomotion, as well as movement of internal organs, such as the contraction of the heart and the movement of food through the digestive system via peristalsis.
Internet Users in the U.S.A. (2016*) 1  Share of U.S. Population: 88.5 % (penetration) 2  Total Population : 324,118,787. 3  Share of World Internet Users: 8.4 4  %. Internet Users in the World: 3,424,971,237.
Main article: Global Internet usage. This is a sortable list of countries by number of Internet users as of 2013. Internet users are persons using the Internet in the last 12 months from any device, including mobile phones. Percentage is the percentage of a country's population that are Internet users. Estimates are derived from either household surveys or from Internet subscription data. Non-country and disputed areas are shown in italics. All United Nations member states are included, except South Sudan and North Korea.