military defense against a possible nuclear attack in the context of the Cold War, is expected to maintain the high command communicated to the country despite a major destruction of their communications networks. Although there was no military application was funded and used by these scientists to communicate and work more comfortably. After his creation was used by the government, universities and other centers academic. The emergence of this network of networks brought countless scientific and technological advantages. Today, Internet is used by all and with the emergence of the World Wide Web (the "Web") or Network World Global expansion has no limits. This has enabled global communication flow on a scale unprecedented in human history. People separated in time and space, can use the Web to exchange or even develop each other's innermost thoughts, or alternatively their attitudes and desires of everyday life.
It is the means of wider dissemination of personal exchange appeared in human history, far ahead of print. This platform has allowed users to interact with many more groups of people scattered around the planet, what is possible within the constraints of physical contact or simply the limitations of all other existing media combined. Thus we can conclude that the emergence of the Internet brought undeniable benefits, it has become a powerful tool for the world, but like all technologies they do, it has also brought many consequences, and make people much more comfortable, work less, and accessible to other unpleasant information because, as a development tool for all can be used for malicious purposes. Internet users usually have defects, generating a large dependence of many things descuidandote personal or work. The network is easy to find good information, while another with different characteristics and unpleasant as pornography, graphic violence, terrorism, which applies particularly to children. It is also presumed to be the main source of piracy have been born with it other evils such as spam, malware, the proliferation of viruses, phishing, etc. a Pienso that computer viruses are human nature: the only way of life we have created so far is purely destructivaa . (Stephen Hawking) This was expressed as current holder of the Lucasian Chair of Mathematics (Lucasian Chair of Mathematics), University of Cambridge and a member of the Royal Society of London, of the Pontifical Academy of Sciences and National Academy of Sciences, USA .
Despite this the benefits of this new technology are endless and its contribution in the field of trade can not be denied. E-commerce seeks to fulfill the needs of clients based on the benefits they seek, which means that the price depends on the enhancement of the customer, not cost, such opportunities arise when offered differ by elements of marketing other than price, which produces value-laden benefits, such as the comfort produced by the direct distribution through electronic software distribution. With all these new concepts are created different paths in the wide world of commerce as are the pages of classified ads. These are places where ads are inserted free on products offered, and in turn can see what they offer others, ie in these places can be customers or vendors at the same time. The most common is that the product range is very wide, because in them we find free classified ads for buying and selling of mobile phones, apartments, houses, cars, computers, motorcycles, jobs, clothing, furniture, conveyances, animals, second hand , all steps from here, and the best is the interaction between the user and the system is extremely simple.