什么是网际网路

公众存取的电脑网路，由来自世界各地许多较小的网路连接而成。产生於美国国防部计画，称为ARPANET（高等研究计画署网路），建造於1969年，连接加州大学洛杉矶分校、史丹福研究所、加州大学圣塔巴巴拉和犹他大学的电脑。ARPANET目的在於研究电脑网路在战争的情况下提供安全无虞的通讯系统。当网路快速扩张，大学院校与其他领域研究人员也加以利用。1971年发展出第一个在分散网路传送电子邮件的程式，1973年建立ARPANET的国际线路（从英国及挪威），电子邮件占去ARPANET大多数的流量。1970年代还见到邮件名单、新闻群组及电子布告栏及TCP/IP通讯协定的发展，後者在1982～1983成为ARPANET的标准协定，导致网际网路的广泛使用。1984年引进网域名称定址系统。1986年美国国家科学基金会建立NSFNET，足以处理更大流量的分散式网路，不到一年就有超过1万主机连上网际网路。1988年由於网际网路中继聊天协定（参阅chat）的发展，在网路上即时交谈成为可能。1990年ARPANET结束，留下NSFNET，第一家商业拨接存取网际网路的公司出现。1991年全球资讯网公诸在世人面前（藉由FTP）。Mosaic浏览器在1993年发行，随着它的普及导致全球资讯网的网站与使用者激增。1995年NSFNET回归研究网路的角色，将网际网路的流量留给网路提供者传递，而不用国家科学基金会的超级电脑。这一年全球资讯网变成网际网路最受欢迎的部分，流量超越FTP协定。1997年时网际网路上有1000万个以上的主机，注册的网域名称超过100万。网际网路存取现在可以藉由无线电波信号、有线电视、卫星、光纤线路，虽然大多数的流量还是利用公众电信（电话）网路。一般认为网际网路对於人类文化与商业的各个层面都有重大的影响，但其机制仍有待厘清。

Internet

Publicly accessible computer network connecting many smaller networks from around the world. It grew out of a U.S. Defense Department program called ARPANET (Advanced Research Projects Agency Network), established in 1969 with connections between computers at UCLA, Stanford Research Institute, UC-Santa Barbara, and the University of Utah. ARPANET's purpose was to conduct research into computer networking in order to provide a secure and survivable communications system in case of war. As the network quickly expanded, academics and researchers in other fields began to use it as well. In 1971 the first program for sending E-mail over a distributed network was developed; by 1973, the year international connections to ARPANET were made (from Britain and Norway), E-mail represented most of the traffic on ARPANET. The 1970s also saw the development of mailing lists, newsgroups and bulletin-board systems, and the TCP/IP communications protocols, which were adopted as standard protocols for ARPANET in 1982-83, leading to the widespread use of the term Internet. In 1984 the domain name addressing system was introduced. In 1986 the National Science Foundation established the NSFNET, a distributed network of networks capable of handling far greater traffic, and within a year more than 10,000 hosts were connected to the Internet. In 1988 real-time conversation over the network became possible with the development of Internet Relay Chat protocols (see chat). In 1990 ARPANET ceased to exist, leaving behind the NSFNET, and the first commercial dial-up access to the Internet became available. In 1991 the World Wide Web was released to the public (via FTP). The Mosaic browser was released in 1993, and its popularity led to the proliferation of World Wide Web sites and users. In 1995 the NSFNET reverted to the role of a research network, leaving Internet traffic to be routed through network providers rather than NSF supercomputers. That year the Web became the most popular part of the Internet, surpassing the FTP protocols in traffic volume. By 1997 there were over 10 million hosts on the Internet and over 1 million registered domain names. Internet access can now be gained via radio signals, cable-television lines, satellites, and fiber-optic connections, though most traffic still uses a part of the public telecommunications (telephone) network. The Internet is widely regarded as a development of vast significance that will affect nearly every aspect of human culture and commerce in ways still only dimly discernible.