Important scientific discoveries of the 20th centuries
Internet
What is the Internet?
The Internet is "a network connecting many computer networks". It is "a loose association of thousands of networks and millions of computers across the world that all work together to share information". The Internet is based on an addressing system and a communications protocol called TCP/IP (Transmission Control Protocol/ Internet Protocol). The Internet was developed in the 1970s to assist the U.S. military and academic research. By 1990, it was still unknown to the general public. By the end of 1995, millions of users with no affiliation to de 12412h714m fense institutions or universities claimed access to the Internet.
What are the components of the Internet?
The Internet pack includes an electronic mail system (e-mail), file transfer, bulletin boards and news groups, remote computer access (telnet) and the World Wide Web (WWW) . The WWW enables navigation of internet sites through a graphical interface, and is therefore considered the most important component of the Internet.
History of the Internet
The Internet started as a program established in 1969 by the U.S. Department of Defense called ARPANET (Advanced Research Projects Agency Network), to insure a secure communications network for organizations involved in defense-related research. At length, researchers and academics in other fields began to benefit from such network. Eventually the National Science Foundation (NSF) -which had already established a similar network called NSFNet- took over much of the TCP/IP technology from APRANET. In 1990, the U.S. government officially discarded ARPANET and the NSF took over the management of the Internet backbone. In 1995, the NSF withdrew and commercial providers -also referred to as Internet Service Providers (ISP's)- took control of whom the GTE, MCI, Sprint, UUNet are the best known. They connect to each other and create a fast "pipeline" that stretches across the U.S.A., extends to Europe, Japan, Asia and the whole world.
Internet and Cyberspace?
At present, the Internet and cyberspace are primarily associated terms and may be regarded as "nearly synonymous terms". Thus "cyberspace" may be defined as "the artificial environment created by the linkage of computer networks through telephone lines, i.e. the Internet." A "cyberspatial environment" increases the intimacy between people in remote places . The Internet indeed has helped support such intimacy and its users are all part of this environment.
Role of the Internet in creating a Global Village
"The Internet encourages the formation of virtual communities without hindrance from national or geographical boundaries." In addition , the Internet facilitates the exercise of freedom of speech since it offers the general public the tools to become publishers, which is an advantage not always warranted by local governments. Nevertheless, these aspects of the Internet have advantages and inconveniences, as follows:
Pros: The Internet unites the remotest regions, bringing people, languages, ideas, thoughts and opinions together. One of the earliest views of the effect of electronic media was expressed by Fedor Dostoyevsky in his novel The Brothers Karamazov (1879-80). He wrote, "We are assured that the world is becoming more and more united, is being formed into brotherly communion, by the shortening of distances, by the transmitting of thoughts through the air."
Cons: The Internet causes widening of the gaps between rich and poor. Those who are capable of using the internet are usually the better educated and wealthier part of the population. Besides, it reduces direct face to face socialization among the people as users turn away from their television or radio sets to indulge into narrow communion with others inhabiting the cyberspatial environment. Moreover, use of the Internet could lead to a violation of civil and privacy rights, since the Internet eases the act of tracking private interests and political beliefs. Other dangers include the violation of intellectual property rights and the extravagant exhibition of pornographic materials.
Future Views of the Internet
The Internet will likely absorb the functions of television, telephone and conventional publishing, thus creating an "information superhighway", as paraphrased by Al Gore Jr. in 1992 -then a senator- in reference to a unified, interactive system of electronic communication. There are plans for establishing a second network that will be referred to as "Internet 2". The reason behind such plan is the traffic jam faced by the users of the current Internet. It is rather obvious from the graph above that there is a growth in Internet use that expands yearly.
Nuclear Energy
"Nuclear Energy is the safest, cleanest, cheapest, and most efficient type of energy." It supplies about 17% of the world's electricity. Nowadays, it has become an issue in a major debate as to whether such type of energy ought to be disposed of, or continued to be used and developed while disregarding its disadvantages.
What is Nuclear Energy?
The structure of the nucleus of an atom can undergo changes. Such changes are called "nuclear reactions". The form of energy produced in a nuclear reaction is referred to as "nuclear energy" or "atomic energy". Nuclear energy is either produced by "nuclear fission" (in which large nuclei are split to release energy) or by "nuclear fusion" (in which small nuclei are combined to release energy). The atomic bomb and nuclear reactors in nuclear plants work on the principle of nuclear fission, where the element uranium (isotope U-235) is used to undergo fission. Stars produce their heat and light through nuclear fusion. The hydrogen bomb operates by nuclear fusion as well.
Advantages
Speaking in terms of limited supplies of energy, nuclear energy is the most efficient alternative to coal, oil and natural gas, which are on their way of becoming scarce.
Nuclear energy has environmental benefits. It is a pure form of energy, the production of which doesn't involve the burning of fossil fuel in no way whatsoever.
Uranium fuel -upon which nuclear power plants run- contains much more concentrated energy than any other fuel. It is estimated that one pound of uranium can produce as much electricity as 12,000 pounds of coal and 1,200 gallons of oil. Therefore, nuclear power plants consume less amounts of fuel than needed by those which burn other fuels, and at the same time they produce additional amounts of electricity, making countries' economies grow.
Nuclear fuel is less costly than other fuels.
For countries that rely on foreign oil suppliers, nuclear energy is good news, for it cuts their demands for imported oil.
Disadvantages
Reactor meltdowns -where the nuclear fission reaction accidentally goes out of control- result in the occurrence of nuclear explosions. A famous reactor meltdown incident took place in Russia's Chernobyl nuclear power plant, where radiation escaped from the reactor to which many lives were exposed. Many died in the following days and others in the following years.
Nuclear explosions cause the emission of massive amounts of harmful radiation. Living organisms exposed to nuclear radiation are subject to life-threatening diseases.
Nuclear waste produced by nuclear reactors- is difficult to be disposed of. Nuclear waste emits harmful radiation that causes harm to living organisms.
Nuclear Weapons
Nuclear weapons, examples of which include the atomic bomb and the hydrogen bomb, are major threats in the field of nuclear physics. It is estimated that the amount of nuclear weapons that exist in the world today is sufficient enough to kill everyone. Those who argue in favour of nuclear weapons believe that they are essential for ensuring security and safety. Indeed, this is true. However, stricter methods should be adopted to control their use.If a nuclear war breaks out, the resultig damage would surely be devastating. We definitely don't want incidents like those which took place in Hiroshima and Nagasaki to occur again.
The Future of Nuclear Energy
Nuclear power plants will undergo major development, making them faster and less costly to build, better performing and safer to the environment and its inhabitants. A convenient solution to the problem of the disposal of nuclear waste will be found. More countries will sign the Nuclear Non-Proliferation Treaty and until then stricter methods will be applied to minimize the likelihood of the use of nuclear weapons. These aren't but a few attempts to make the world a safer place for all, and a better environment where Man is able to prosper and develop.
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