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How The Internet Works How The Internet Works By: Taty Sena simplytatydesigns.com Edited by: Justin Pot JustinPot.com This manual is intellectual property of MakeUseOf. It must only be published in its original form. Using parts or republishing altered parts of this guide is prohibited without permission. http://simplytatydesigns.com | Taty Sena MakeUseOf.com Page 2 How The Internet Works Table of Contents Introduction .............................................................................................................................. 5 1. A brief history of the Internet .............................................................................................. 5 Early Development .............................................................................................................. 6 Current................................................................................................................................... 8 2. Transfering Information ....................................................................................................... 9 Computers ............................................................................................................................ 9 Cable ..................................................................................................................................... 9 ISPs (Internet Service Providers) ......................................................................................... 9 Hosts, Servers....................................................................................................................... 10 IPs (Internet Protocol) Addresses ..................................................................................... 10 DNS (Domain Name System) ........................................................................................... 11 URLs ...................................................................................................................................... 12 3. The Basic Languages and Protocols of the Web .......................................................... 13 HTML ..................................................................................................................................... 13 PHP, ASP and Databases .................................................................................................. 14 XML....................................................................................................................................... 15 Flash ..................................................................................................................................... 16 Java ..................................................................................................................................... 16 Ajax ...................................................................................................................................... 16 4. Who runs the Internet?...................................................................................................... 17 ICANN .................................................................................................................................. 17 W3C ..................................................................................................................................... 18 IANA ..................................................................................................................................... 18 5. Current Internet Trends ..................................................................................................... 18 Online Media (Newspapers, Magazines) ....................................................................... 18 Multimedia .......................................................................................................................... 19 Social Networks .................................................................................................................. 20 Wi-Fi ...................................................................................................................................... 21 Mobile Internet ................................................................................................................... 21 6. How the Web Changed the World ................................................................................. 22 The past decade ............................................................................................................... 23 STATS ......................................................................................Error! Bookmark not defined. http://simplytatydesigns.com | Taty Sena MakeUseOf.com Page 3 How The Internet Works Who they are .................................................................................................................. 25 Most used hardware worldwide .................................................................................. 25 Number of websites worldwide.................................................................................... 25 Most popular sites worldwide ....................................................................................... 25 Other fun web facts ....................................................................................................... 26 Conclusion .............................................................................................................................. 26 http://simplytatydesigns.com | Taty Sena MakeUseOf.com Page 4 How The Internet Works Introduction It is impossible to deny the influence of the Internet. In the 1990’s it quickly changed from an exciting technology few understood to something so prevalent most can’t imagine living without it. The World Wide Web is a powerful thread that connects the entire world, one that allows us to share information like never before. The benefits of accessing so much information are too many to list, and while some problems are also becoming apparent, the web’s place in our daily lives is undeniable. We can now access the Internet from our home computers, office, laptops and our phones. But even with this close intimacy many people still aren’t entirely sure what the Internet is and how it really works. This guide explores these questions, starting with a bit of history. 1. A brief history of the Internet Like most revolutionary ideas, the Internet started with a few people who dared to dream the impossible. The year was 1962 and Leonard Kleinrock (pictured) at MIT had just published the first paper on packet switching theory, which was the technology that allows information to be transferred as packets of information. At the same time, a man named J.C.R. Licklider of MIT wrote a series of memos describing a "Galactic Network," which would allow people to access information from anywhere. The story could have ended there. But, as it happens, Licklider was the first head of the computer research program at DARPA (the research and development office for the U.S. Department of Defense), and convinced his successors that researching networking processes was an important undertaking. http://simplytatydesigns.com | Taty Sena MakeUseOf.com Page 5 How The Internet Works In 1965, MIT researcher Lawrence G. Roberts, along with Thomas Merrill, connected the TX-2 computer in Massachusetts to the Q-32 in California with a low speed telephone line. This project, sponsored by ARPA, intended to study a "cooperative network of time-sharing computers‖. That was the first time a long distance computer network was created, and it helped show researchers that it could work— although it also showed them how inadequate phone lines were for the transmission of information. In 1966, using the knowledge he had acquired from his previous experiment, Roberts put together plans for the creation of the ―ARPANET‖, which would eventually become the modern ―Internet‖. Early Development The development of the ARPANET was not without major glitches. Charley Kline at UCLA sent the first packet ever using the network as he tried to connect to Stanford Research Institute on Oct 29, 1969. The first word he tried was LOGIN, but the system crashed when he reached the letter G. http://simplytatydesigns.com | Taty Sena MakeUseOf.com Page 6 How The Internet Works By 1972 Ray Tomlinson created email for the ARPANET and started using the symbol ―@‖ for email addresses. In 1973, a protocol called FTP (File Transfer Protocol) was created to allow files to be transferred to hosts as sites (more on that below). That is the protocol used today to upload files to servers and websites. By 1981, Listserv software made the exchange of information easier, and by the 1980’s, the first private ISP (Internet Service Provider) appeared. The Internet started to become broadly used in the 1990’s. The first search engine— Archie, from McGill University in Montreal—was created. This was followed in 1991 by WAIS and Gopher. Lycos was created in 1993 and Yahoo was founded in 1994, but the major change in how people searched the web happened in 1998, with the launch of a clean and efficient little search engine called Google. http://simplytatydesigns.com | Taty Sena MakeUseOf.com Page 7 How The Internet Works Current Although Google cannot be credited with the development of the web since the late 1990’s, it serves as a major turning point in its popular acceptance. Within a short time, ―to Google‖ would become a verb synonym to searching the web. During the 90’s major investments had been made in the field of technology, and investors and companies saw the web as the new portal for their investments. So many of those investments went badly that 2000 is known as the year the dot-com bubble burst, with the majority of the high investment dot-coms going down during 2001 and 2002. The irony of the dot-com bubble burst is that the Internet would, in the years after the burst, prove itself immensely profitable and a major focus of investments once again. It matured to become such a part of people’s lives that it had begun to threaten the existence of companies that refused to create a strong presence online. http://simplytatydesigns.com | Taty Sena MakeUseOf.com Page 8 How The Internet Works 2. Transferring Information Computers From the users’ end, computers are a direct link to the Internet. A computer with Internet access is necessary for retrieving files served by websites. Most computers are adequate for that task, but naturally as the web grows more and more complex so does the computing power needed to take advantage of it. Cables There are currently a few different types of cables that can be used to connect a computer to the Internet. The most common ones are phone lines (for DSL and modem users) and Broadband RJ-45 (ethernet) cables. The phone line can connect users to a modem connection directly, or be connected to a router for DSL users, and then to an RJ-45 cable. Broadband cable and T1 users don’t use a phone line, but use HFC and RFoG networks instead. ( Left to right, RJ connectors: an eight-pin RJ-45 plug, six-pin RJ-25 or RJ-12 plug, four-pin RJ-11 or RJ-14 plug, and a four-pin RJ-22 (RJ-10 or RJ-9) handset plug) ISPs (Internet Service Providers) Internet service providers are the companies that you pay to get Internet delivered to your house or workplace, such as Time Warner Cable, Comcast or Verizon DSL. They are the links between you and the large network we call the Internet, so by paying a fee they can give you access to their infrastructure and connect you to other computers. What you are really paying for is for the usage of their hardware: their cables, computers, routers, modems, the workers who maintain them and the real estate that is required to hold that hardware. http://simplytatydesigns.com | Taty Sena MakeUseOf.com Page 9 How The Internet Works The Internet itself and the information stored in it is, for the most part, free; without an ISP, however, you would not have access to it. Hosts, Servers The information you see online needs to be stored by computers called hosts, or servers, which are constantly sending the information to the World Wide Web. Most major web hosting companies have huge buildings with hundreds or thousands of servers to store the websites they host. When you type a website address on your browser, they receive the request and send out the information that appears on your browser. You can turn your own computer into a server, but it would probably serve the pages slowly if many people are trying to access the site at once. IPs (Internet Protocol) Addresses Websites, computers on a network and hosts are identified by a series of numbers called IP addresses. Even your computer has an IP address; you can find it by visiting sites such as http://whatismyipaddress.com/ Websites have public IP addresses, which are their identifiers online. For example, we all know that to reach Google, you can type Google.com on the address bar. Google’s real IP is 66.102.7.99 , so if you type that on the address bar, you will also find Google. This is how it works: Let’s say your address is 125 Happy Street, but you decide to put a sign on your door that says ―Bob’s House‖, which covers the street number. You can then tell your friends to look for ―Bob’s House‖, which would be easier for them to remember, but your real address still is 125 Happy Street. In this analogy, then, ―Bob’s house” is your Domain Name (below) and 125 Happy Street is your IP number. http://simplytatydesigns.com | Taty Sena MakeUseOf.com P a g e 10