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CSIS-390 Some Web History. Dr. Eric Breimer. How it came to be…. Before developing web applications it is important to know these two things evolved. Internet World Wide Web (WWW). Are these things the same?. Internet. World Wide Web. ARPA net.
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CSIS-390Some Web History Dr. Eric Breimer
How it came to be… • Before developing web applications it is important to know these two things evolved • Internet • World Wide Web (WWW)
Are these things the same? • Internet • World Wide Web
ARPAnet • ARPANETAdvanced Research Projects Agency • 1969, Cold War, Military Applications
ARPAnet • Originally, network applications for sharing data and messages 1968-1973 • 1971 Email concept developed • Person can have an identifier name@network • Virtual mailbox • By 1973 Email was 75% of the ARPAnet traffic • File Transfer Protocol (FTP) was developed in 1973
ARPAnetInternet • Transition Period 1971-1983 • Packet Switching developed and perfected • Instead of point-to-point persistent connections • Robust, fault-tolerant, efficient, survivable • Network of Networks realized on a large scale • The ability to connect different types of networks TCP/IP
Early Internet 1983-1989 • No web browsers, no web pages at all… • Only… • Email • FTP (document and image sharing) • Early message board systems (BB systems) • Custom client-server applications • Banking • Early business to business E-commerce
In 1989 came the WWW • The concepts existed, but one man implemented the concepts and made them real… • WWW concepts • Hypertext concept – Documents can have links to other documents, just click the text • URL concept – Documents, computers, virtual mailboxes, networks can all have uniform identifier to help locate them
Tim Berners-Lee (TBL) • Programmed the first widely-used • web browser • web server • which formalized the • HTTP protocol, and • HTML as a standard language • Also, prompted the widespreaduse of • URLs
Before the WWW, finding stuff was hard • To find data on the Internet you had to • Know numeric IP addresses to locate FTP servers • Login anonymously or with a user account • Know the folder hierarchy and file name of the document/data. • People would share this information via Email. • browsing the Internet was no possbile, you just couldn’t do it. • Only “insiders” had access to stuff.
Understanding the WWW • HTTP instead of FTP • Web Browser instead of FTP client • Web Server instead of FTP server • URLs instead of numeric IP addresses • Clicking Hyperlink instead of navigating through folder hierarchies • HTML instead of postscript (meant for print typesetting) and plain text documents.
So these are not the same thing… Internet • Physical network • Hardware • TCP/IP • Packet Switching • Network of Networks concept World Wide Web • The content • Software • HTTP • URLs • Hyperlinks
WWW Infancy1989-1995 • 1989 TBL invents first web browser and server • 1991-93 Al Gore proposes a bill that funds major Internet initiatives. • Money spent on new fiber optic national network • Mosaic(first good graphical web browser) was a funded project • InterNIC, which eventually becomes ICANN, is another notable product of the Gore Bill. • By 1995, Internet traffic moves off NSFnetand on to commercially operated networks (Verizon, UUNet, Sprint, AT&T, and Genuity) • ARPAnet NSFnet Internet II
WWW Commercialization Period 1995-2000 • 1995 – Netscape become a household name • Sells web server software…gives away browser for free • Reached almost 90% market share by 1996 • 1995 – 1996 Microsoft scrambles to come out with competing software (Internet Explore and Web Server) • 1996-1999 – Browser Wars between Microsoft and Netscape • Two versions of HTML are used in practice • Browser specific plug-ins become the norm: Flash, RealMedia, etc. • 1997-2000 – E-commerce Commercial Explosion • Amazon, E-bay, Online Stock Trading, MP3 trafficking, etc.
Browser Wars 1996-1999 • Microsoft (Internet Explorer) and Netscape compete to be the #1 browser. • In ’96 Netscape dominated • By ‘99 Internet Explorer was #1 • Microsoft Integrated IE into the Windows OS • Forced upon people as the default browser • Microsoft paid billions in lawsuit (EU mostly) but still won the war • Netscape makes its source code open, so developers can build upon it. • Leads to the Mozilla Foundation, which eventually develops Firefox. • In 2000, AOL buys out Netscape, which is was failing financially • This marks the end of the war and beginning of Microsoft’s dominance in the WWW.
Browser Wars - Significance • Early competition pushed web browsers to the limit. • Browsers use to be simple client applications that could render HTML code. • Browsers became heavy-weight applications • Microsoft’s dominance was terrible. • Use proprietary (secret) languages and often fought against establishing open standard languages.
Why Standards? Advantages • Accessibility • Forward Compatibility • Simpler and Faster Development • Faster Download & Display
Why Standards? • Accessibility • Forward Compatibility • Simpler and Faster Development • Faster Download & Display • Standardized web pages look good (and sound good) on all browsers and devices • Device to consider: • B&W Kindle • Cheap Smartphone • Computer connect to Jumbotron at Stadium • Screen readers for the visually impaired
Why Standards? • Accessibility • Forward Compatibility • Simpler and Faster Development • Faster Download & Display • Future standards are built on top of current standards • A forward compatible design can accept data from a future version of itself and pick out the "known" part of the data. • text-only browser ignoring <img> tag from a future version. • An extensible design is one that can be upgraded to fully handle the new input format. • An example is a text-only word processor that can be upgraded to handle picture data.
Why Standards? • Accessibility • Forward Compatibility • Simpler and Faster Development • Faster Download & Display • Faster: You don’t have to build separate websites for separate browsers/devices • Concurrent Development:Content and style can be developed separately by different teams.
Example: <center> <b> <font face="Georgia, Times New Roman, Times, serif" color=“#880000" size="+2">Sub-title</font></b></center> Why Standards? • Accessibility • Forward Compatibility • Simpler and Faster Development • Faster Download & Display • Style/Appearance tags are bloated • Rather than load bloated HTML for every page, just load one style sheet for an entire website
Rendering Engines • Browsers can have two or more rendering engines • Example: parsing standard and non-standard HTML code. • The <!doctype>and <html> tag tells the browser which engine to use. <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
Rendering Engines & Validation • Validated HTML code can be rendered faster. • Rendering engine doesn’t have to handle special cases and errors • Non-standard HTMLwill cause a rendering error • Browser will re-render using a more forgiving “error correcting” engine. • Don’t you wish Java had an “error correcting” compliler?
Validate Validate Validate • http://validator.w3.org/ • It’s a pain but… • At least you know that your web page will display properly on about 400 different browser variations.
Who cares if the rendering engine is a little slow? • True, on modern PCs you won’t notice the difference. • However, consider that the device rendering the web page could bea tiny device with a 133 MHz processor.
Standards: The Big Motivation • Consider how many different smart phones exist • Each uses a slightly different variation of Safari, Chrome, or some special browser. • W3C wants web developers to follow the rules so browsers do not have to be overly complex • W3C wants browser developers to follow the rules so web page look as similar as possible on different devices.
Some key things to remember: • TBL is the most under-rated inventor in the last 100 years. • Web Browsers weren’t always so consistent but they may be in the future. • Device-specific apps may not survive if the W3C can continue to innovate.
Tim Berners-Lee (TBL) • Widely recognized as the inventor of • HTML (perfecting the concept of hypertext) • URLs (paving the way for web browsing) • Implemented first web browser (text based) and web server (unix daemon). • Should be a billionaire but then the WWW wouldn’t be so cool and free. • I love the man! You should love him too.
Web Browser History • 1991: TBL makes the first web browser in his physics labs. Dr. B gets his braces off and discovers Clearasil. • 1993: Mosaic (the first real graphical browser) is built. Free, open source, works for Mac’s, Windows, and UNIX. The birth of free porn. • 1994: Netscapeemerges and starts to sell a lot of software. • 1995: Microsoft wakes up, makes a browser, and tries to monopolize the market.
Browser History • 1996-1999: BrowserWars…different versions of JavaScript, CSS, and HTML emerge. While standards go down the toilet…at least a lot cool sh*t was developed. • 1998: Microsoftintegratesits browser into Windows 98 and 2000 making it #1. • before dying Netscape makes its code Open Sourceallowing developers to build upon it. • 2000: Microsoft wins! Netscape gets bought by AOL. The .com Bust happens!Dr. B contemplates becoming a pop star but then decides to be a professor.
Browser History • 2002: Kelly Clarkson (not Dr. B) wins American Idol! • 2003: Programmers who once worked for Netscape form the Mozilla Foundation • 2005: Firefoxstarts to make a serious dent in Microsoft’s monopoly. • 2006: Developers start to follow the standards instead of Microsoft • CSS is revitalized. • 2012: Chrome is poised to overtake IE, which has been #1 for nearly 15 years.