人人终身学习知识网~是各类综合知识资源信息分享,提升综合素质与提高知识技能的终身学习网络平台

 找回密码
 立即注册

QQ登录

只需一步,快速开始

微信登录

微信扫码,快速开始

[职称英语阅读理解] 2015年职称英语《理工类》阅读理解练习题(5)

[复制链接]

 people tend to think of computers as isolated machines,working away all by themselves.some do-personal computer without an outside link,like someones hideaway cabin in the woods.but just as most of homes are tied to a community by streets,bus routes and electric lines,computers that exchange intelligence are part of a community m local,national and even global network joined by telephone connections.

  the computer network is a creation of the electric age,but it is based on old-fashioned trust.it cannot work without trust.a rogue loose in a computer system called hacker is worse than a thief entering your house.he could go through anyones electronic mail or add to,change,distort or delete anything in the information stored in the computers memory.he could even take control of the entire system by placing his own instructions in the software that runs it.he could shut the computer down whenever he wished,and no one could stop him.then he could program the computer to erase any sign of his ever having been there.

  hacking,our electronic-age term for computer break-in,is more and more in the news-brainy kids vandalizing university records,even pranking about in supposedly safeguarded systems.to those who understand how computer networks are increasingly regulating life in the late 20th century,these are not laughing matters.a potential for disaster is building: a dissatisfied former insurance-company employee wipes out information from payroll files.a student sends out a virus,a secret and destructive command,over a national network.the virus copies itself at lightning speed,jamming the entire networkthousands of academic,commercial and government computer systems.such disastrous cases have already occurred.now exists the possibility of terrorism by computer.spoiling a system responsible for air-traffic control at a busy airport,or knocking out the telephones of a major city,is a relatively easy way to spread panic.yet neither business nor government has done enough to toughen its defenses against attack.for one thing,such defenses are expensive; for another,they may interrupt communication the main reason for using computers in the first place.

回复

使用道具 举报

小黑屋/人人终身学习知识网~是各类综合知识资源信息分享,提升综合素质与提高知识技能的终身学习网络平台

Powered by 5wangxiao

© 2007-2021 5wangxiao.Com Inc.

快速回复 返回顶部 返回列表