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Cyberculture: The Internet and Popular Culture. Fall 2009.
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Cyberculture: The Internet and Popular Culture. Fall 2009 This work, and all other files in this course, are licensed under the Creative Commons Attribution License. To view a copy of this license, visit http://creativecommons.org/licensesor send a letter to Creative Commons, 171 2nd Street, Suite 300, San Francisco, California, 94105, USA. These slides are best viewed with “slide show”. To print the slides, consider using "File/Print/Properties/Pages per sheet" instead of Power Point's "handouts" mode. Slides will be ready by 6PM each Monday evening. If not, send email to len. Len Shapiro, len at pdx.edu Syllabus: http://www.cs.pdx.edu/~len/345
Contents • Motivation • Tool Classes • Counting • What is a computer? • Networks and Communications • The Internet and its history • The Web • Resources, Browsers, URLs, Web Servers, • Links, Anchors, Hypertext • Principles of the Web
Motivation • The Internet has changed how you play, think, shop… • I want you to become Internet Experts • Just as Obama hired Internet Experts, and raised 100s of millions of dollars http://tinyurl.com/copupy • Just as a car jock can get cheaper repair jobs • You will study different classes of Internet tools • For each tool you will • Become a knowledgableuser of one tool in that class • Understand how the tool works • Understand the principles underlying this class of tools
Tool Classes • Here are the classes of tools we will study • Collaborative Documents • Search Engines • Social Networks • Entertainment • Blogs • Folksonomies • Business Tools • Virtual Worlds • Tools to protect your privacy • Now we study the fundamentals.
Fundamentals: How do we count? • Bit: 0 or 1 • Byte: 8 bits. Holds one character • Kilobyte (1024 bytes), • Megabyte (1024 Kilobytes) • Gigabyte (1024 Megabytes) • Terabyte (1024 Gigabytes) • Petabyte (1024 Terabytes) • Exabyte (1024 Petabytes) (Some sources use 1000 in place of 1024)
Counting for real • Imagine a byte as one grain of rice • Then a kilobyte is less than a page of text, or a bowl • A megabyte is a short novel, or a 50lb sack of rice • A gigabyte is a full length movie or 2 shipping containers of rice • A terabyte is a major library or a container ship of rice. • A petabyte is 80 bowls of rice for every person on theplanet, or covering a major city a yard deep in rice.
Examples of Counting • Library of congress: 20 terabytes • YouTube streams 200 terabytes per day • Facebook stores over 1.5 petabytes of user data. • Data processed by Google servers per hour: 1 petabyte • All works of humankind,in all languages: 50 petabytes • http://www.nytimes.com/2006/05/14/magazine/14publishing.html • Monthly Internet traffic: 5-8 exabytes • http://en.wikipedia.org/wiki/Exabyte
What is a Computer? • Central Processing Unit – CPU – does the computing. • Memory – remembers. • Cache memory is on the chip with the CPU, in kilo/megabytes • other memory is off the CPU chip, in mega/gigabytes • Input • Keyboard, mouse, touch, wire, etc • Output • Screen, dial, wire, etc. • Storage • Longer term memory. Disk, tape, flash.
Networks* • A network is any group of computers that communicates with each other. • What are some examples of networks? *An asterix in the title means there is info in the notes view
Communications Protocols • A CommunicationsProtocol is an agreed-upon set of rules for communicating. • What are some rules for the protocol of human conversation? • If you exchange names, you shake hands • Don't stand too close or too far away • Computer communications protocol rules include introduction, data representation, and error correction. • The most popular computer communication protocol is called TCP/IP.
What is the Internet? • The Internet is a global system of interconnected computer networks that uses TCP/IP. • The Intenet supports myriad applications, including the world wide web, email, chat, social networks, wikis, file sharing, gaming, and gambling.
History of the Internet* • In the 60s, RAND corporation worried about how US authorities could communicate after a nuclear war. • Existing networks, like the phone system, had two problems • Central hubs: destroy one hub and the network is down • Virtual circuits: cut a connection and its conversation is gone • RAND proposed packet switching; the Army bought it. • Data is split into small packets • Each packet finds the best path from source to destination • The result is decentralized • An attack on a few nodes does not cripple the network. • In 1969, ARPANET had 4 nodes.
Internet History, ctd. • Already by year 2, ARPANET was used mainly for email! • In the 70s, TCP/IP became the standard communications protocol for ARPANET. • TCP/IP was public domain software and during the 80s and 90s many other networks used it and connected themselves to ARPANET. • This was easy because of decentalization. • ARPANET became a small part of the Internet. • In 1983, military applications broke off from ARPANET into MILNET, and in 1989 ARPANET disappeared.
Internet History, ctd. • In the 80s, the Internet organized itself into domains with suffixes like .com, .edu, .org, .gov and 2-character country codes. • In the 90s, the WWW hit:
Resources, Browsers • "Some internetresources can be accessed with a browser." • Example browsers include Internet Explorer, FireFox, and Safari • Let's look at some example resources: • A Static HTML page: http://www.cs.pdx.edu/~len/345/index.html • The /index.html can be omitted • View the source: in your browser, click view/source • A Dynamic HTML page: http://www.amazon.com • It's dynamic because it is personalized • A Video: youtube.com/watch?v=KxmHmYiVQ64 • Note the abbreviation. http://www is missing. Most browsers can handle this • An Email address: mailto:len@psu.edu • Note that the scheme is mailto. What does it do?
URLs, Web Servers • The label, used by a browser to locate the resource, is called a Uniform Resource Locator, or URL. • A URL begins with a scheme, typically a protocol, such as http or mailto . • The rest of the URL, typically an address, is processed according to the scheme to find the resource. • This processing is done by a program called a Web Server.
A URL in Detail* • http://www.cs.pdx.edu/~len/345/index.html • http – the scheme, or protocol • Tells the web server how to process the address • : - separates the scheme from the address • pdx.edu – the domain name. • www.cs – the name of the local machine in that domain • ~len – len's home directory on that machine • 345 – a subdirectory in len's home directory • index.html – an html file in that subdirectory
The Web: Visual The server www.pdx.edu Your browser, with www.pdx.edu in the address area The web server inside www.pdx.edu HTTP request Your browser, displaying the index.html file The file index.html Generates <html> <head> … </html>
Links, Anchors • A Link is an embedded URL that can be clicked with a mouse. • Let's try some links. • Two slides previous • The syllabus • The result, of clicking a link, is: • the same as pasting the URL in a browser • to display the resource referenced/pointed to by the URL. • called dereferencing the URL • you don't surf to it, it comes to you! • The link may be represented by an anchor. • In the syllabus, Intro.ppt is the anchor representing the URL www.cs.pdx.edu/~len/345/Intro.ppt
Hypertext* • Hypertext is text (or any file) that contains link(s). • What are some examples of hypertext?
The World Wide Web (WWW)* • The World Wide Web is all hypertext on the internet. • What does it mean to surf the web? • Let's investigate the difference between the Internet and the WWW. • Are Wikipedia pages part of the WWW, the Internet? • Are Email documents part of the WWW, the Internet? • Are Word Processor documents part of the WWW, the Internet?
History of the WWW* • 1945: Vannevar Bush writes an article "As we may think", that presages many of the ideas of the WWW: http://www.theatlantic.com/doc/194507/bush • 1960s: Doug Englebart (from OSU) invents the mouse and hypertext and Ted Nelson coins the word hypertext. • In 1980 Tim Brenners-Lee invents links between machines. • In 1990 Tim writes the first browser, coins the word WorldWideWeb. • 1992: 26 servers on the WWW. • 1994: over 200 web servers, Netscape founded, first WWW conference, WWW Consortium founded
First Assignment • Now let's look at the syllabus and review the first assignment
Principles of the WWW • The Web works – its applications succeed – because of a few basic principles. • These principles change with time and with authors, but one of their best descriptions is Tim O'Reilly's "What is Web 2.0" http://tinyurl.com/743r5 • This article may not make much sense to you now • The next few pages are my versions of these principles • They will become clearer as the course progresses and we discover more Internet applications • The principles are in no particular order
Principle 1: Data Rules* • The value of an application is increased by the scale and dynamism of the data it manages • Scale: size, amount • Dynamism: how current and relevant is the data? • Data can be web pages, audio, video, • What applications can you think of which illustrate this principle?
Principle 2: The Long Tail* • Small products/ideas make up the great majority of all products/ideas. • Chris Anderson, Wired Magazine, 2004:http://tinyurl.com/d7f7k • What applications use the Long Tail principle?
Principle 3: Use your Users* • Enable users to contribute content to the application. User content can be the most valuable type of data. • What applications embody this principle? • It doesn’t always work: • Google is losing money, big time, on YouTube • http://www.newsweek.com/id/205984 • Content can be falsified. • Company ordered its employees to write positive reviews. Fined $300,000.http://www.nytimes.com/2009/07/15/technology/internet/15lift.html?hpw
Principle 4: The Power of Groups* • Apply the wisdom of users to solve problems. In certain situations, groups can be wiser than experts. • Which applications embody this principle? • An excellent book on this topic is Infotopia, by Cass Sunstein
Principle 5: Enable Community* • Enable users to share their experiences in your application • Which applications embody this principle? • Applications which embody the Power of Groups principle necessarily embody this principle, but not conversely.
Principle 6: Folksonomy, not Taxonomy* • Utilize user-generated tags to classify items, instead of expertly generated categories • Pre-web, scholars always used categories, organized in hierarchies, to classify phenomena. Computers enable the management of tags. • A taxonomy is a classification into categories. A folksonomy is a classification using tags. • What are some applications that use tags? • There's not a big difference between tags and keywords…
Browsers • What browsers do you use? • Major players: Safari, IE, Firefox, Chrome, Opera • http://www.pcworld.com/article/150828/browser_battle_firefox_31_vs_chrome_vs_ie_8.html is a good discussion of the pros and cons of each player • Major trick: ctrl-t to open a new tab
Next Week • Choose discussion articles