International electronic mail systems are no longer the plaything of hackers

游客2024-06-08  12

问题     International electronic mail systems are no longer the plaything of hackers and bug-eyed computer enthusiasts. They are emerging as credible business tools that enable individuals and companies to communicate cheaply and efficiently around the globe.     Like the in-house electronic mail networks that have become a fact of business life in many companies, these systems provide a means of sending and receiving messages via personal computers or computer terminals. With global electronic mail services, however, messages can be sent across the world or across town.
    For evidence of the rising popularity of electronic mail, a look at the business cards collected from clients or contacts lately should be enough. The chances are that some of them include electronic mail "addresses" along with telephone and fax numbers.
    The advantages of electronic mail are numerous. It can eliminate hours of frustrating "telephone tag" and enable people to communicate across time-zones with ease. It also substitutes for busy fax machines that print out piles of paper which are often misplaced or misdirected. With electronic mail, the message appears upon the computer screen of the individual being contacted.
    The biggest roadblock to the success of electronic mail in the past has been the lack of sufficient users. Although dozens of personal computer electronic mail services are available, until recently they were not linked. This meant that to reach somebody it was necessary to subscribe to the same electronic messaging system.
    Over the past couple of years, however, many electronic mail systems have started "talking" to one another. The mechanism for this is "Internet"--a low-cost and efficient link between electronic mail services worldwide.
    Internet links an estimated 1.5 million computers over 10,000 networks in 50 countries, serving about six million users. Internet resembles a computer network cooperative. There is no central authority that oversees it, and rules are largely informal.     Over the past 20 years it has mushroomed to include regional, corporate and public networks, including commercial electronic mail systems. "People conduct their love life over Internet, their hobbies and their interests. They argue polities and engage in all kinds of business,’ says Mr. Mitch Kapor, co-founder of Electronic Frontier Fountain of Cambridge, Massachussetts, which promotes awareness of the on-line world.
    Despite the anarchic nature of its structure, the basics of using Internet communications are simple. All that is needed is a computer, a modem, a communications software package and a subscription to an on-line information service linked to Internet.
    Subscription costs range from about US$9 to US$20 per month, depending on the service and varying according to the information services offered.
    Once a subscription to one of these services is obtained, the charge for sending an electronic message is generally only a few cents. In most places a local telephone call will connect you to the system. [br] Why was electronic mail unsuccessful in the past ?

选项 A、Because its users subscribed to different, unconnected mail services.
B、Because people thought its services expensive.
C、Because people couldn’t afford the personal computer.
D、Because computer networks used to disconnect globally.

答案 A

解析 参见文章第5段的第2、3、4行:Although dozens of personal computer electronic mail services are available,until recently they were not linked.(尽管可以使用许多个人计算机电子邮件网络,但直到最近,它们才连接到一起)和This meant that to reach somebody it was necessary to subscribe to the same electronic mes
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