The Internet and Telecommunications教案
the internet and telecommunications教案module 6 the internet and telecommunications
話題導入
電腦網絡是我們日常生活中的重要工具,如果沒有了它,這個世 界不知會變得如何?電腦網絡能處理的事情太多了,衣、食、住、行、吃、喝、玩、樂、電子采購、電子公文交換、電子支付、電子保健、電子監理等等,都和電腦脫不了關系,它還能把事情整理得井井有條。在以后的歲月中,不懂電腦網絡的人很可能寸步難行!
背景知識
the first computer
世界上第一臺電子數字式計算機于1946年2月15日在美國賓夕法尼亞大學正式投入運 行,它的名稱叫eniac(埃尼阿克),是電子數值積分計算機(the electronic numberical integrator and computer)的縮寫。它使用了17468個真空電子管,耗電174千瓦,占地170平方米,重達30噸,每秒鐘可進行5000次加法運算。雖然它的功能還比不上今天最普通的一臺微型計算機,但在當時它已是運算速度的絕對冠軍,并且其運算的精確度和準確度也是史無前例的。
computer network
將地理位置分散的計算機通過專用的電纜或通信線路互相連接,就組成了計算機網絡。網絡可以使分散的各種資源得到共享,使計算機的實際效用提高了很多。計算機聯網不再是可有可無的事,而是計算機應用中一個很重要的部分。人們常說的因特網(internet,也譯為國際互聯網)就是一個通過通信線路連接、覆蓋全球的計算機網絡。通過因特網,人們足不出戶就可獲取大量的信息,與世界各地的親友快捷通信, 進行網上貿易等等。
引入型閱讀
tim berners-lee and the internet
tim berners-lee is the man who wrote the software(軟件) programme that led to the foundation of the world wide web.britain played an important part in developing the first generation(第一代) of computers.the parents of tim berners-lee both worked on on e of the earliest commercial(商業的) computers and talked about their work at home.as a child he would build models of computers from packaging material.after graduating from oxford university he went on to the real thing.in the 1980’s,scientists were already using a primitive version(原始版本) of e-mail.while working at a laboratory in swi tzerland tim berners-lee wrote a programme which let him store these messages.in 1990 he wrote the http(服務程序所用的協議) and html(超文本鏈接標示語言) programmes which formed the basis o f the world wide web.
the next year his programmes were placed on to the internet.everyone was welcome to use them and improve them if they could.programmers used his codes(編碼) to work with different operating systems (系統).new things like web browsers(瀏覽器) and search engines were developed.between 1991 and 1994 the number of web pages rose from 10 to 100 000.
in 1994 tim berners-lee formed the newly-formed world wide web co nsortium(協會) or w3c.more than 200 leading companies and laboratories are represented(代表) by w3c.t ogether they make sure that everyone can participate(參加) equally on the web.