Most of the technology for teleconferencing already exists. Key componentsare terminals connected to computer systems and a video system that allows pictures to be transmitted from one spot to another. Local area networks are unifying much of the traditional equipment found in the office. The purpose of a local area network is to electronically connect word processing， electronic mail， voice storage and forwarding， dictation， and even coping machines together.
Computers are now helping us in almost every area of science and engineering. Over half of the world’s scientific knowledge has been obtained since the construction of the first electronic computer. While business applications require the handling of a large number of documents， the scientific community requires speed and accuracy in making complex computations. The average individual can make from 5 to 10 simple computations per minute. The average computer can make 10，000 complex computations per second， and fast computers can make millions of complex calculations per second. Computations that would take a computer a few seconds would take you a few months or even a few years.
Computers can be used to help astronomers test physics theories. They are also needed to help forecast complicated and unpredictable weather patterns.
Computers can also process and enhance images or pictures. This is called image processing. Image processing is using the computer to enhance and gain a better understanding of images or pictures. It can be used to develop cartoons， touch up photographs， and generate movies. Digitized images are sent to earth receiving stations， and the images are processed. Satellites like Landsat are able to locate oil fields， help farmers determine what to plant， locate mineral deposits， locate ships， missiles， and military installations， and more.
Computers are widely used in health care too. Small inexpensive personal computers， costing under a thousand dollars， have been used in ambulances to locate invalids or other patients quickly. These personal computers have also been used to diagnose potential problems and prescribe their remedies at the scene of an accident. Video games have been developed to allow you to play games and lose weight at the same time. Some software program can help you to relieve stress and tension.
At home， computer can be used to entertain you， educate you， keep track of your personal budget， plan meals， and determine what food items to buy for the next week. You can use personal computers to communicate with friends， relatives， or business associates anywhere in the world as long as they also have personal computers and access to an electronic mail network. Personal computers can be used as the centers of sophisticated security systems. These computers can be sensitive to heat， smoke， water damage， and more. They can be programmed to call you automatically at another phone number or to call the police or the fire department.
Computers are extensively used in the entertainment and leisure industry. Computers are used to analyze and create beautiful musical sounds and tones. You can even get novel sent to you electronically over telephone lines using home computers. These electronic novels can be stored in your computers and then printed at any time.
In education， with computer-aided instruction （CAI）， the computer is being used to help students learn other subjects. CAI programs are available today for people ranging in age from one year old to well past retirement age. You are never too young or too old to learn.
In the military， computers are being used to design both conventional and strategic weapons. These military computers are special purpose computers—expensive computers designed to perform only one function.
Computers are working everywhere now.
【Vocabulary】
witness
vt. 目睹，作证
dramatic
adj. 戏剧性的，生动的
investment
n. 投资，可获利的东西
inventory
n. 存货，详细目录
alert
n. 警报，提醒
estate
n. 状态，不动产，阶层
weld
n. 焊接，接缝 vt. 焊接
depreciation
n. 贬值，减价，跌落
wholesale
n. 批发 adj. 批发的
warehouse
n. 仓库，货栈
postal
adj. 邮政的，邮局的
diagnose
vt. 诊断
scene
n. 现场，场面，情景，景色
astronomer
n. 天文学家
invalid
n. 病人，伤残者
remedy
n. 药物，疗法 vt. 治疗，补救
sophisticate
vt. 篡改，曲解，诡辩 n. 久经世故的人
leisure
n. 空闲，闲暇，安逸
available
adj. 可利用的，有用的
retirement
n. 退休，撤退
military
adj. 军用的，军事的
strategic
adj. 战略的，战略上的
perform
vt. 旅行，执行，表演
split-second
adj. 瞬间发生的，片刻的
【参考译文】
计算机的应用
现在我们正目睹着当今发展最迅猛的技术之一——计算机的发展。
计算机被用于各种规模的商业，政府教育，医疗保健及其他几乎所有的行业。
计算机被用于几乎所有的商业领域。在投资业，使用计算机可以得到最新的股票证券行情，以便作出瞬间的买断决定。在房地产与金融业，计算机可以用来调查现金流动、投资回收和贬值等情况。银行利用计算机处理每天进行的大量的支票和信用卡交易。没有计算机，今日的银行便无法处理每秒进行的大量业务。在制造业，计算机用来设计新产品、控制生产设备并管理存货和其他原材料。计算机被用来自动下订单，在库存可能缺货时提醒客户，帮助经营管理生产运作的各个方面。计算机控制的机器人用在喷漆、焊接、加固以及装配线的组装上。计算机还用在零售与批发上，在零售方面，计算机在杂货店、五金店和百货商店快速地收款；它们还被用来确定零售与批发点；也能快速有效地制定工厂库房、批发商店以及零售商店之间的最佳运输方式。
计算机对办公程序有着深远的影响。有了文字处理，公司能够将重要的段落进行电子存档，然后再把它们调出来，以各种想象的形式重新组织安排后打印。有些文字处理程序配有收词量在10万词以上，可以自动检查拼写和语法的词典。电子邮件是办公自动化的又一激动人心的革新，起着信箱和邮政服务的作用。计算机迅速地把信息分发给相应的人。有了声音存储与传送，人们能用电话接通计算机给其他人留下指令和信息。一旦存储，这些口头信息能够被高效自动地抄录并打印出来。它们能被存储起来以备将来使用参考，也能用电子邮件发送到世界各地。把传真机作为一台复印机，原件放进此地的传真机中，在另一地的传真机上便会出现原件的复印件。
远距离通信会议的大部分技术已经具备。主要的构成是终端与计算机系统连接，然后录像系统把图像从一地传到另一地，局域网把办公室的传统设备连为一体。局域网的目的是高效自动地将文字处理、电子邮件、声音存储和发送、发布命令，甚至把复印机也统统连接起来。
现在计算机几乎在科学和工程的每个方面给我们提供帮助。自从第一台电子计算机问世以来，我们获得了世界一半以上的科学知识。由于商业应用需要处理大量的文件，科学领域要迅速准确地进行复杂的运算，普通人每分钟能做5到10个简单运算，一般的计算机每秒能做1万个复杂运算。快速的计算机每秒能做几百万个复杂运算。用计算机运算只需几秒钟而用人则要几个月甚至几年的时间。
计算机可以用来帮助天文学家检验物理理论，人们还需要计算机来帮助预报复杂多变的气候结构。
计算机还能处理和增强图像与画图的效果，称为图像处理。图像处理就是用计算机来提高并更好地理解图像与画面。图像处理可以用于开发动画、润色照片、生产电影。数字图像被送到地面接收站进行处理。像 Landsat 这样的卫星能确定油田的位置；帮助农民决定种什么；确定矿物沉淀的位置；确定船、导弹、军事装备等的位置。
