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CSIS-401: Web Design Dr. Breimer CSIS-401: Web Design Dr. Breimer

Some Background & History 1. Web Design is a diverse field 2. Standards are Some Background & History 1. Web Design is a diverse field 2. Standards are important • 4 reasons 3. Web Design is going “old school” • Separation of structure and style. 4. Internet Explorer isn’t the only browser? • Browser History

Definition • Web design is the design of websites and web applications using HTML, Definition • Web design is the design of websites and web applications using HTML, CSS and images.

Definition • Websites can be very diverse. E-trade Playhouse Disney Facebook Protein Databank Definition • Websites can be very diverse. E-trade Playhouse Disney Facebook Protein Databank

Web Design Career #1 Visual Designer • Uses – Adobe Photo. Shop, – Fireworks, Web Design Career #1 Visual Designer • Uses – Adobe Photo. Shop, – Fireworks, – Flash, etc. • Expertise in graphic design, layouts, color theory, etc.

Web Design Career #2 Interface Designer • Expertise in – graphical programming, – human Web Design Career #2 Interface Designer • Expertise in – graphical programming, – human computer interaction and – interfaces • Background in behavioral science, ergonomics, etc.

Web Design Career #3 Software Developer • Most modern software has web-based components. • Web Design Career #3 Software Developer • Most modern software has web-based components. • Most new applications are entirely webbased. • Programmers need to know HTML, CSS, etc.

Web Design Career #4 Database Administrator • Almost all Databases interface with web technologies. Web Design Career #4 Database Administrator • Almost all Databases interface with web technologies. • Large website are entirely database-driven. • Database Administrators also need to know HTML, CSS, XML, etc.

Web Design Career #5 Web Master/Web Authoring • Larger websites require extensive content management. Web Design Career #5 Web Master/Web Authoring • Larger websites require extensive content management. • Developing and managing content is a specialty. • Writing conventions and styles are different on the web.

Web Design Career #6 Marketing & Advertising • Online marketing is an entire field. Web Design Career #6 Marketing & Advertising • Online marketing is an entire field. • Web technology can help marketers achieve new innovations. • Marketers & Advertisers need to know about fundamental web technologies.

HTML • Hyper. Text Markup Language • A simple text document can be “markedup” HTML • Hyper. Text Markup Language • A simple text document can be “markedup” with tags to specify how it should be interpreted. • Level 1 Header

HTML • HTML was supposed to be a structural or “semantic” language, – But, HTML • HTML was supposed to be a structural or “semantic” language, – But, the Browser Wars lead to the introduction of “style” or formatting tags. – “style” tags are bad! – They are being removed from the HTML standards (called deprecation).

CSS • Cascading Style Sheets • Used to specify the style/appearance of structural elements CSS • Cascading Style Sheets • Used to specify the style/appearance of structural elements (HTML tags). • CSS was part of the original design of the web, • but its use was almost entirely abandoned between 1997 and 2003.

Why are “style” tags bad? • The best answer is very complicated • Short Why are “style” tags bad? • The best answer is very complicated • Short Answer: – Leads to bloated HTML code that is hard to maintain.

Semantic vs Style Semantic = Has Meaning Style = Specifies Appearance Semantic vs Style Semantic = Has Meaning Style = Specifies Appearance

Semantic vs Style Semantic Meaning Style Appearance <img src=“tiger. jpg”> <span class=“caption”> This is Semantic vs Style Semantic Meaning Style Appearance This is a picture of a tiger This is a picture of a tiger A caption is meaningful. Images typically have a caption that describes the image. Here, we specify how to display the caption but not the fact that it’s actually a caption.

Semantics + CSS is better! <span class=“caption”>Figure 1</span> <span class=“caption”>Figure 2</span> <span class=“caption”>Figure 3</span> Semantics + CSS is better! Figure 1 Figure 2 Figure 3Figure 99. caption { font-size: 10 pt; font-style: italic; }

This is why the font tag sucks! (it’s a style tag) <font type=“Arial” style=“italic” This is why the font tag sucks! (it’s a style tag) Figure 1 Figure 2 Figure 3 Figure 999 Sub-title Imaging if you wanted to change the font size to 12 pt for all image captions? Good luck!

History Lesson: The Good Times • Standardization was very important in the initial design History Lesson: The Good Times • Standardization was very important in the initial design of HTML (1991 -1994) – Initially, HTML was structural/semantic – The presentation of web pages was left up to the user, via web browser settings. • Netscape & Microsoft created “evil” tags ( for example) so that web page designers could control the presentation of their web pages.

History Lesson: Browser Wars • Netscape & Microsoft added many proprietary enhancements to HTML History Lesson: Browser Wars • Netscape & Microsoft added many proprietary enhancements to HTML (1994 -1999) – Proprietary == Only works for a specific browser – Proprietary == Not Open == Not standard • Web authors would use HTML tags to control the visual presentation, but pages would look completely different on different browsers. • In 1998, the web development community and W 3 C said “Enough is enough” • www. webstandards. org was formed

W 3 C – What is it anyway? • The World Wide Web Consortium W 3 C – What is it anyway? • The World Wide Web Consortium (W 3 C) – international consortium of web developers – sub-organizations, full-time staff, and regular people • Work together to develop Web standards • Mission: – To lead the World Wide Web to its full potential by developing protocols and guidelines that ensure long-term growth for the Web. www. w 3. org

Current Web Standards • Structural Standards – XHTML 1. 0 – This is actually Current Web Standards • Structural Standards – XHTML 1. 0 – This is actually HTML 4. 01 rewritten according to XML standards. – XML – set of rules for creating custom markup languages. • Presentation Standards – CSS 1 (Since 1996) fully supported by almost all browsers – CSS 2 current standard, extends CSS 1 – CSS 3 the future, extends CSS 2

Current Web Standards • Behavioral Standards – Document Object Model (DOM) – allows programs Current Web Standards • Behavioral Standards – Document Object Model (DOM) – allows programs to control HTML documents. • Each part of an HTML document has a name • Each part can be manipulated by name – Java. Script – uses the DOM to manipulate web pages on the client’s browser. – PHP, JSP, ASP, Cold. Fusion, etc. can use the DOM to manipulate web pages on the web server

Why Standards? Advantages 1. Accessibility 2. Forward Compatibility 3. Simpler and Faster Development 4. Why Standards? Advantages 1. Accessibility 2. Forward Compatibility 3. Simpler and Faster Development 4. Faster Download & Display

Why Standards? 1. Accessibility 2. 3. Forward Compatibility Simpler and Faster Development Faster Download Why Standards? 1. Accessibility 2. 3. Forward Compatibility Simpler and Faster Development Faster Download & Display 4. • Standardized web pages look good on all browsers. • And on all different types of devices. – Cell phones – PDA’s – Screen readers for the visually impaired

Why Standards? 1. Accessibility 2. Forward Compatibility 3. Simpler and Faster Development Faster Download Why Standards? 1. Accessibility 2. Forward Compatibility 3. Simpler and Faster Development Faster Download & Display 4. • Future standards are built on top of current standards • Thus, Web pages made today will work in the future Note: • Browser Wars created html tags that were not standard • These tags won’t display properly in many “standard” browswers. • Internet Explorer and Firefox still support these tags, but not for long.

Why Standards? 1. 2. Accessibility Forward Compatibility 3. Simpler and Faster Development 4. Faster Why Standards? 1. 2. Accessibility Forward Compatibility 3. Simpler and Faster Development 4. 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.

Why Standards? 1. 2. 3. Accessibility Forward Compatibility Simpler and Faster Development 4. Faster Why Standards? 1. 2. 3. Accessibility Forward Compatibility Simpler and Faster Development 4. 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 • Example:

Sub-title

Rendering Engines • Browsers actually have different rendering engines for parsing standard and non-standard Rendering Engines • Browsers actually have different rendering engines for parsing standard and non-standard HTML code. • The or tag tells the browser which engine to use.

Rendering Engines • Standard, validated HTML code can be rendered faster. – Rendering engine Rendering Engines • Standard, validated HTML code can be rendered faster. – Rendering engine doesn’t have to handle special cases and errors • Most web browsers can display Nonstandard HTML, – but a more complex rendering engine must be used – More complex mean slower rendering.

Who cares if the rendering engine is a little slow? • True, on modern 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 be cell phone with a 33 MHz processor.

Standards: Big Motivation • Without standards, you would have to test how your website Standards: Big Motivation • Without standards, you would have to test how your website looked on many different browsers. 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. Microsoft IE 67% Mozilla Firefox 19% Apple Safari 9% Google Chrome 2% Netscape < 1% Opera < 1% AOL Explorer Amaya Camino Epiphany Maxthon Shiira Hot. Java Nintendo DS Play. Station PWB Lynx Voyager Micro Browser Omniweb

Standards: Big Motivation 1. 2. 3. 4. Microsoft IE 67% Mozilla Firefox 19% Apple Standards: Big Motivation 1. 2. 3. 4. Microsoft IE 67% Mozilla Firefox 19% Apple Safari 9% Google Chrome 2% • Not a problem: 96% of the world uses four browsers. • But, more and more people are browsing on different devices • Consider cell phones, PDA’s, GPS devices, and even refrigerators… – All use different browser variations. • W 3 C wants the web to fully work on any kind of device. – Even today, many websites won’t display properly on small devices.

Internet-enable devices • Portable Media Players – To buy music • Automobiles – To Internet-enable devices • Portable Media Players – To buy music • Automobiles – To send info to mechanics • Refrigerators – To buy more groceries • What will they think of next?

Validate • http: //validator. w 3. org/ • It’s a pain but… • At Validate • http: //validator. w 3. org/ • It’s a pain but… • At least you know that your web page will display properly on about 400 different browser variations.

Tim Berners-Lee (TBL) • Widely recognized as – The inventor of HTML – First Tim Berners-Lee (TBL) • Widely recognized as – The inventor of HTML – First implementor of hypertext concept – Implemented first web browser (text based) and more importantly, first web server (unix daemon). • Should be a billionaire but then the WWW wouldn’t be so cool! • I love the man! You should love him too.

Web Browser History • 1991: TBL makes the first web browser in his physics 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: Netscape forms, they develop a browser and immediately start adding proprietary tags. • 1995: Microsoft wakes up, makes a browser, and decides they need to monopolize the browser market

Browser History • 1996 -1999: Browser Wars…different versions of Java. Script, CSS, and HTML Browser History • 1996 -1999: Browser Wars…different versions of Java. Script, CSS, and HTML emerge. While standards go down the toilet…at least a lot cool sh*t was developed. • 1998: Netscape screws Microsoft in a big way by making its code Open Source. Microsoft fights back by integrating its browser into the Windows 98 and 2000. • 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: Browser History • 2002: Kelly Clarkson (not Dr. B) wins American Idol! • 2003: Some managers who once worked for Netscape form the Mozilla Foundation • 2005: Firefox busts out on the scene. First browser to make a serious dent in Microsoft’s monopoly. • 2006: Dr. B finally learns CSS.

Summary • Originally HTML was meant to be a structural/semantic language • The Browser Summary • Originally HTML was meant to be a structural/semantic language • The Browser wars lead to the destandardization of HTML. – Proprietary style tags were added. • Standardization and semantic HTML has made a comeback – Old school web design is back!