什么是互聯(lián)網(wǎng)
什么是互聯(lián)網(wǎng)
互聯(lián)網(wǎng)是由一些使用公用語(yǔ)言互相通信的計(jì)算機(jī)連接而成的網(wǎng)絡(luò),即廣域網(wǎng)、局域網(wǎng)及單機(jī)按照一定的通訊協(xié)議組成的國(guó)際計(jì)算機(jī)網(wǎng)絡(luò)。接下來(lái)小編為大家整理了什么是互聯(lián)網(wǎng)。希望對(duì)你有幫助哦!
The Internet is a giant network of computers located all over the world that communicate with each other.
The Internet is an international collection of computer networks` that all understand a standard system of addresses and commands, connected together through backbone systems. It was started in 1969, when the U.S. Department of Defence established a nationwide network to connect a handful of universities and contractors. The original idea was to increase computing capacity that could be shared by users in many locations and to find out what it would take for computer networks to survive a nuclear war or other disaster by providing multiple path between users. People on the ARPNET (as this nationwide network was originally called) quickly discovered that they could exchange messages and conduct electronic "conferences" with distant colleagues for purposes that had nothing to do with the military industrial complex. If somebody else had something interesting stored on their computer, it was a simple matter to obtain a copy (assuming the owner did not protect it)。
Over the years, additional networks joined which added access to more and more computers. The first international connections, to Norway and England, were added in 1973. Today thousands of networks and millions of computers are connected to the Internet. It is growing so quickly that nobody can say exactly how many users "On the Net".
The Internet is the largest repository of information which can provide very very large network resources. The network resources can be divided into network facilities resources and network information resources. The network facilities resources provide us the ability of remote computation and communication. The network information resources provides us all kinds of information services, such as science, education, business, history, law, art, and entertainment, etc.
The goal of your use of the Internet is exchanging messages or obtaining information. What you need to know is that you can exchange message with other computers on the Internet and use your computer as a remote terminal on distant computers. But the internal details of the link are less important, as long as it works. If you connect computers together on a network, each computer must have a unique address, which could be either a word or a number. For example, the address of Sam's computer could be Sam, or a number.
The Internet is a huge interconnected system, but it uses just a handful of method to move data around. Until the recent explosion of public interest in the Internet, the vast majority of the computers on the Net use the Unix operating system. As a result, the standard Unix commands for certain Internet services have entered the online community's languages as both nouns and verbs to describe the services themselves. Some of the services that the Internet can provide are: Mail, Remote use of another computer (Telnet), File Transfer (FTP), News, and Live conversation.
The most commonly used network service is electronic mail (E-mail), or simply as mail. Mail permits network users to send textual messages to each other. Computers and networks handle delivering the mail, so that communicating mail users do not have to handle details of delivery, and do not have to be present at the same time or place.
The simplest way to access a file on another host is to copy it across the network to your local host. FTP can do this.
Presently, a user with an account on any Internet machine can establish a live connection to any other machine on the Net from the terminal in his own office or laboratory. It is only necessary to use the Unix command that sets up a remote terminal connection (Telnet), followed by the address of the distant machine.
Before you can use the Internet, you must choose a way to move data between the Internet and your PC. This link may be a high-speed data communication circuit, a local area network (LAN), a telephone live or a radio channel. Most likely, you will use a Modem attached to your telephone line to talk to the Internet. Naturally, the quality of your Internet connection and service, like many other things in life, is dictated by the amount of money that you are willing to spend.
Although all these services can well satisfy the needs of the users for information exchange, a definite requirement is needed for the users. Not only should the users know where the resources locates, but also he should know some operating commands concerned to ease the searching burden of the users, recently some convenient searching tools appears, such as Gopher, WWW and Netscape.
World wide web (www) is a networked hypertext protocol and user interface. It provides access to multiple services and documents like Gopher does but is more ambitious in its method. A jump to other Internet service can be triggered by a mouse click on a "hotlinked" word, image, or icon on the Web page.
As more and more systems join the Internet, and as more and more forms of information can be converted to digital form, the amount of stuff available to Internet users continues to grow. At some points very soon after the nationwide (and later worldwide) Internet started to grow, people began to treat the Net as a community, with its own tradition and customs. For example, somebody would ask a question in a conference, and a complete stranger would send back an answer: after the same question were repeated several time by people who hadn't seen the original answers, somebody else gathered list of "frequently asked questions" and placed it where newcomers could find it.
So we can say that the Internet is your PC's window to the rest of the world.
Internet是由位于世界各地相互通信的計(jì)算機(jī)連接而成的巨大的計(jì)算機(jī)網(wǎng)絡(luò)。
Internet 是計(jì)算機(jī)網(wǎng)絡(luò)的國(guó)際性的集合,這些網(wǎng)絡(luò)都符合具有地址和命令的標(biāo)準(zhǔn)體系,并經(jīng)骨干網(wǎng)連在一起。Internet始建于1969年,當(dāng)時(shí)美國(guó)國(guó)防部為連接少數(shù)幾所大學(xué)和協(xié)議企業(yè)而建立了一個(gè)全國(guó)性網(wǎng)絡(luò)。最初的想法是要增加計(jì)算機(jī)能力并可由許多地點(diǎn)的用戶共享,并且通過(guò)提供用戶間多條路徑來(lái)找到哪一種計(jì)算機(jī)網(wǎng)絡(luò)能夠在核戰(zhàn)或其他災(zāi)難中幸存。ARPNET(這種全國(guó)網(wǎng)絡(luò)最初的名稱)上的用戶很快就發(fā)現(xiàn)他們可以與遠(yuǎn)距離的同事交換消息,并且進(jìn)行某種目的的電子“會(huì)議”,而這些目的與軍事工業(yè)企業(yè)沒(méi)有任何關(guān)系。如果另外一些人在其計(jì)算機(jī)中存有有趣的東西,得到其拷貝是很容易的事(假定擁有者沒(méi)有進(jìn)行保護(hù))。
幾年間,新的網(wǎng)絡(luò)接入使越來(lái)越多的計(jì)算機(jī)加入進(jìn)來(lái)。在1973年進(jìn)行了第一次與挪威和英國(guó)的國(guó)際連接。今天,有成千上萬(wàn)的計(jì)算機(jī)網(wǎng)絡(luò)和數(shù)百萬(wàn)臺(tái)計(jì)算機(jī)與Internet相連。Internet發(fā)展如此之快以至于沒(méi)有人能準(zhǔn)確地說(shuō)出網(wǎng)上有多少用戶。
Internet是最大的信息寶庫(kù),它可以提供非常巨大的網(wǎng)絡(luò)資源。這種網(wǎng)絡(luò)資源可分為網(wǎng)絡(luò)設(shè)備資源和網(wǎng)絡(luò)信息資源。網(wǎng)絡(luò)設(shè)備資源使我們能夠進(jìn)行遠(yuǎn)程計(jì)算和通信。網(wǎng)絡(luò)信息資源向我們提供各種各樣的信息服務(wù),如科學(xué)、教育、商務(wù)、歷史、法律、藝術(shù)和娛樂(lè)等等。
使用Internet的目的是交換消息或獲得信息。你只須知道你可以與Internet上的其他計(jì)算機(jī)交換消息并將你的計(jì)算機(jī)用作遠(yuǎn)端計(jì)算機(jī)的遠(yuǎn)程終端,而鏈路的內(nèi)部細(xì)節(jié)并不太重要,只要網(wǎng)絡(luò)能工作就行。若將多臺(tái)計(jì)算機(jī)連接到網(wǎng)絡(luò)上,每臺(tái)計(jì)算機(jī)須有惟一的地址,地址可以是一個(gè)字或一個(gè)數(shù)字。例如Sam的計(jì)算機(jī)地址可以是Sam或一個(gè)數(shù)字。
雖然Internet是一個(gè)巨大的互聯(lián)系統(tǒng),但它僅使用一點(diǎn)簡(jiǎn)單辦法就將數(shù)據(jù)傳來(lái)傳去。近來(lái)公眾對(duì)Internet產(chǎn)生了極大的興趣,在這之前,絕大多數(shù)網(wǎng)上計(jì)算機(jī)都使用Unix操作系統(tǒng)。結(jié)果,用于某些Internet業(yè)務(wù)的標(biāo)準(zhǔn)Unix命令已經(jīng)進(jìn)入聯(lián)機(jī)團(tuán)體語(yǔ)言當(dāng)作名詞和動(dòng)詞來(lái)描述業(yè)務(wù)本身。 Internet可以提供的一些服務(wù)為:電子郵件、遠(yuǎn)程使用其他計(jì)算機(jī)、文件傳送、電子新聞和實(shí)況對(duì)話。
最常使用的網(wǎng)絡(luò)服務(wù)是電子郵件,或簡(jiǎn)稱郵件。電子郵件允許網(wǎng)絡(luò)用戶彼此傳送文本消息。郵件的傳遞由計(jì)算機(jī)和網(wǎng)絡(luò)處理,郵件用戶不必關(guān)心傳遞的細(xì)節(jié),也不必同時(shí)在場(chǎng)。
從其他主機(jī)中獲得文件的最簡(jiǎn)單的方式是通過(guò)網(wǎng)絡(luò)將其拷貝到你的計(jì)算機(jī)上。文件傳送(FTP)可完成這項(xiàng)工作。
目前,用戶在Internet建立賬戶后,就可從其辦公室和實(shí)驗(yàn)室的終端上與網(wǎng)上其他計(jì)算機(jī)建立實(shí)時(shí)連接。只需使用Unix命令Telnet來(lái)建立遠(yuǎn)程終端連接,命令后跟上遠(yuǎn)端計(jì)算機(jī)的地址即可。
在使用Internet之前,必須使用一種方法在你的PC機(jī)和Internet之間傳送數(shù)據(jù)。這種連接的鏈路可以是高速數(shù)據(jù)通信電路、局域網(wǎng)(LAN)、電話線路或無(wú)線信道。最有可能的是,你使用Modem連到電話線上與Internet對(duì)話。當(dāng)然,像生活中許多其他的事物一樣,與Internet連接和服務(wù)的質(zhì)量是由你所花錢的數(shù)量決定的。
雖然所有這些服務(wù)可以很好地滿足用戶對(duì)信息交換的需要,但用戶仍舊還需要具有一些特定的先決條件。用戶不僅要知道信息資源所處的位置,而且要知道一些有關(guān)的操作命令。為了減輕用戶尋找信息的負(fù)擔(dān),近來(lái)出現(xiàn)了一些方便的搜索工具,如Gopher,WWW和Netscape.
全球網(wǎng)(WWW)是一種網(wǎng)絡(luò)的超文本協(xié)議和用戶界面。像Gopher一樣,它提供多種服務(wù)和文件接入方法,但其方法更加有前途。向Internet其他服務(wù)的跳轉(zhuǎn)可在“網(wǎng)”頁(yè)上由鼠標(biāo)器點(diǎn)擊“熱鏈接”的字、圖像或按鈕來(lái)啟動(dòng)。
隨著越來(lái)越多的系統(tǒng)加入Internet,同時(shí)隨著越來(lái)越多的信息可以轉(zhuǎn)變成數(shù)字形式,Internet用戶所能得到的東西也在繼續(xù)增加。隨著國(guó)家(后來(lái)是國(guó)際)Internet的發(fā)展,很快在某些方面人們開(kāi)始將互聯(lián)網(wǎng)看作是一個(gè)社區(qū),有自己的傳統(tǒng)和習(xí)慣。例如某些人會(huì)在會(huì)議上提出一個(gè)問(wèn)題,一個(gè)完全陌生的人會(huì)傳送一個(gè)答案;由于一些人沒(méi)有看到最初的答案而多次重復(fù)這一問(wèn)題,這時(shí)另外一些人會(huì)搜集一系列“經(jīng)常提到的問(wèn)題”并將其放置在新來(lái)者能找到的地方。
所以我們可以說(shuō),Internet是你的PC機(jī)通向世界其他地方的窗口。