Communicating Through Internet The history of the Internet can be dated back to the 1960’s, when the Department of【1】______

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问题                   Communicating Through Internet
    The history of the Internet can be dated back to the
1960’s, when the Department of【1】______ of America sought             【1】______
to【2】______ together some research institutions and those across      【2】______
the country for the purpose of data sharing. In the 1970’s it
was used【3】______ by colleges and universities and some               【3】______
other research institutions. It developed rapidly in the 1980’s
as more and more universities joined the net. In the early
90s, HTML and Mosaic were develped with which one could
see【4】______ real time off the Internet, rather than downloading      【4】______
them. Email is an important【5】______ of the Internet, but now         【5】______
the World Wide Web is increasingly the largest part of
our Internet【6】______.                                                【6】______
With the web e-commerce—electronic commerce came
into being. Compared to newspapers, radio and television,
the Internet made【7】______ far less expensive. What’s more,           【7】______
it provided far more detailed data collection and allowed
for built-in electronic【8】______. All this made commerce the          【8】______
driving force for the Internet and World Wide Web.
The Internet changes all the time and yet provides
no complete【9】______. Finding information has been made easier        【9】______
by such attempts as gopher, hotlists, Yahoo and many
others. Generally we use commonly searched terms. Most of
the search【10】______ use double quotation marks to designate          【10】______
a phrase to narrow down the search. Now meta-search
engines have been developed. They speed up searches quite a
bit and provide more complete searches.
【5】
Communicating Through Internet
   Today we’re going to be talking about the brief history of the Internet, and particularly the development of the World Wide Web, and also introduce you to finding your way around the Internet.
   As you may recall, in the 1960’s the Department of Defense recognized the need to link together those research institutions that were working on DOD projects. And in particular they were interested in linking those across the country so that they could share blueprints and other data on satellite, submarine, etc. The Internet continued to grow in the 1970’s and was used largely by college and universities and some other research institutions. And in the 1980’s, the Internet began to pick up speed as more and more universities joined the net. It continued to grow and it seemed to be growing rather rapidly, But little did we know how much faster the Internet in fact would grow. Well, beginning at the end of 1990 and 1991 and 1992, Tim Berners-Lee developed HTML-the hypertext markup language—and Marc Andreeson developed Mosaic, which was a graphical web browser using HTML. What was important was that by the development of HTML and the simultaneous development of a software tool that integrated HTML—one could see images real time off the Internet, rather than downloading them. And so the Internet then became much more than it had been in the past, and in fact, even now we must realize the Internet is more than just the World Wide Web. Email of course is an important component of the Internet. But now the World Wide Web is increasingly the largest part of our Internet experience.
   Before the web, File Transfer Protocol was the mode of access and transfer of information across the World Wide Web. Suppose one would transfer an image, let’s say a satellite image from a government site, say the national weather service to your home computer. Using a separate piece of software on your home computer you would be able to bring up the image. That process took several minutes—that’s much longer than it currently does. Modems of the time were transferring data at 300 baud or 1200 baud. Now, with ISDN lines, 128,000 bit per second is not uncommon.
   Well, the web itself was the beginning of e-commerce—electronic commerce. The potential was envisioned once the web was developed and Internet was no longer just the purview for colleges, universities and researchers. Commercial entities understood the potential of the Internet and when they compared the Internet to newspapers, radio and television for advertising they found the Internet was far less expensive. It provided far more detailed data collection on those who visited the site—and it allowed for built-in electronic ordering—it had so many features that newspaper, radio and TV had only promised. Commerce now drives the Internet and it really is the force that moves the Internet and World Wide Web forward.
    No one person knows what all is on the Internet—it changes every hour, every minute, every second, and there’s no complete index. You know years ago even in the 1980’s when I was teaching classes on new technologies and we talked about the Internet, we described it as going to the Library of Congress with all of the books on the floor and no card catalog. The first attempt came with a process called gopher, which was developed by the University of Minnesota. And then there were hotlists. In fact, a couple of grad students at Stanford developed one that ended up on its own as Yahoo! Web crawlers ultimately came about, such as AltaVista, Infoseek, HotBot, and there are so many others. These web crawlers operate 24 hours a day, 365 days a year and they search domains constantly, they use hot--short for robot-electronic robots that search the Internet going from domain to domain and then they collect information from millions, actually tens of millions, of sites, and yet each of these only covers a fraction of the Internet.
   Well, as you use those web crawlers, you use commonly searched terms. And the way in which you use those terms differ somewhat with each and every web crawler or search engine. Most of the search engines use double quotation marks to designate a phrase if you want those words in that specific order, and that helps you to narrow your search if you put a particular phrase in quotation marks. Generally one avoids uppercase—not always, but generally that will limit one’s search.
   Perhaps the most exciting recent development has been the development of the recta search engines. The meta-crawlers are the crawler of crawlers. That is, it’s a search engine that will then search other search engines. So if you submit a search term to one site, it re submits that term to multiple other search engines and then comes back with the results. Meta-crawlers speed up searches quite a bit. They also provide more complete searches, and of course we are going to be talking more about that, as you see on your syllabus, in greater detail next week.

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