听力原文： Good morning, everyone. Today I'll talk about the Internet. The Internet is a computer-based worldwide information network. The Internet is composed of a large number of smaller interconnected networks called internets. These internets may connect hundreds or thousands of computers, enabling them to share information with each other and to share various resources, such as powerful super computers and databases of information. The Internet has made it possible for people over the world to effectively and inexpensively communicate with each other. Unlike traditional broadcasting media, such as radio and television, the Internet is a decentralized system. Each connected individual can communicate with anyone else on the Internet, can publish ideas, and can sell products with a minimum overhead cost. In the future, the Internet may have a dramatic impact on higher education and business as more universities offer courses and more companies offer goods and services on-line. The internets from which the Internet is composed are usually public access networks, meaning that the resources of the network can be shared with anyone logging onto, or accessing the network. Other types of internets, called intranets, are closed to public use. Intranets are the most common type of computer network used in companies and organizations where it is important to restrict access to the information contained on the network. During the 1990s, the Internet has grown tremendously in the number of people using it and the amount of information contained on it. According to the Internet Society, a non-profit society that studies and promotes the use of the Internet, 134 countries had full Internet connection and an additional 52 countries had limited access( for example, E-mail only)in 1996. Some surveys found that as of September 1997 there were between 53 and 57 million users of the Internet worldwide. Which of the following is true about the Internet according to the talk?