Web Development & Design Foundations with HTML5 8th Edition PDF

Web Development & Design Foundations with HTML5 8th Edition CHAPTER 1 KEY CONCEPTS Copyright © Terry Felke-Morris http://terrymorris.net 1  Learning Outcomes...

Web Development & Design Foundations with HTML5 8th Edition CHAPTER 1 KEY CONCEPTS Copyright © Terry Felke-Morris http://terrymorris.net 1  Learning Outcomes In this chapter, you will learn how to ◦ Describe the evolution of the Internet and the Web ◦ Explain the need for web standards ◦ Describe Universal Design ◦ Identify benefits of accessible web design ◦ Identify reliable resources of information on the Web ◦ Identify ethical use of the Web ◦ Describe the purpose of web browsers and web servers ◦ Identify networking protocols ◦ Define URIs and domain names ◦ Describe HTML, XHTML, and HTML5 ◦ Describe popular trends in the use of the Web Copyright © Terry Felke-Morris http://terrymorris.net 2  Internet The interconnected network of computer networks that spans the globe. Copyright © Terry Felke-Morris http://terrymorris.net 3  Reasons for Internet Growth in the 1990s ◦ Removal of the ban on commercial activity ◦ Development of the World Wide Web by Tim Berners-Lee at CERN ◦ Development of Mosaic, the first graphics-based web browser at NCSA ◦ Personal computers were increasingly available and affordable ◦ Online service providers offered low-cost connections to the Internet Copyright © Terry Felke-Morris http://terrymorris.net 4  The World Wide Web The graphical user interface to information stored on computers running web servers connected to the Internet. Copyright © Terry Felke-Morris http://terrymorris.net 5  Internet Standards & Coordination ◦ IETF – Internet Engineering Task Force ◦ The principal body engaged in the development of new Internet protocol standard specifications. ◦ RFC – Requests for Comments A formal document from the IETF that is drafted by a committee and subsequently reviewed by interested parties ◦ IAB – Internet Architecture Board Provides guidance and broad direction to the IETF. Responsible for publications for RFCs. Copyright © Terry Felke-Morris http://terrymorris.net 6  Internet Standards & Coordination ICANN - The Internet Corporation for Assigned Numbers & Names ◦ Non-profit organization ◦ Main function is to coordinate the assignment of: ◦ Internet domain names ◦ IP address numbers ◦ Protocol parameters ◦ Protocol port numbers. Copyright © Terry Felke-Morris http://terrymorris.net 7  Growth of the Internet Source: http://www.internetworldstats.com/emarketing.htm Year Percentage of Global Population Using the Internet 1995 0.4% 2000 5.8% 2005 15.7% 2010 28.10% 2015 42.4% Copyright © Terry Felke-Morris http://terrymorris.net 8  Intranet & Extranets Intranet ◦ A private network contained within an organization or business used to share information and resources among coworkers. Extranet ◦ A private network that securely shares part of an organization’s information or operations with external partners Copyright © Terry Felke-Morris http://terrymorris.net 9  Web Standards and the W3C Consortium W3C – World Wide Web Consortium ◦ Develops recommendations and prototype technologies related to the Web ◦ Produces specifications, called Recommendations, in an effort to standardize web technologies ◦ WAI – Web Accessibility Initiative ◦ develops standards and support materials to help you understand and implement accessibility. ◦ Provide resources to make your websites, applications, and other digital creations more accessible and usable to everyone. Copyright © Terry Felke-Morris http://terrymorris.net 10  Web Accessibility Accessible Website ◦ provides accommodations for individuals with visual, auditory, physical, and neurological disabilities WAI ◦ W3C’s Web Accessibility Initiative http://www.w3.org/WAI WCAG ◦ Web Content Accessibility Guidelines http://www.w3.org/WAI/WCAG20/quickref/ Copyright © Terry Felke-Morris http://terrymorris.net 11  Web Accessibility & The Law Americans with Disabilities Act (ADA) ◦ Prohibits discrimination against people with disabilities Section 508 of the Rehabilitation Act ◦ Requires that government agencies must give individuals with disabilities access to information technology that is comparable to the access available to others ◦ http://www.section508.gov Copyright © Terry Felke-Morris http://terrymorris.net 12  Universal Design for the Web Universal Design ◦ the design of products and environments to be usable by all people, to the greatest extent possible, without the need for adaptation or specialized design http://www.ncsu.edu/www/ncsu/design/sod5/cud/about_ud/about_ud.htm Copyright © Terry Felke-Morris http://terrymorris.net 13  Reliability & Information on the Web Questions to Ask: ◦ Is the organization credible? ◦ How recent is the information? ◦ Are there links to additional resources? ◦ Is it Wikipedia? Copyright © Terry Felke-Morris http://terrymorris.net 14  Checkpoint 1.1 Describe the difference between the Internet and the Web. Explain three events that contributed to the commercialization and exponential growth of the Internet. Is the concept of universal design important to web developers? Explain your answer. Copyright © Terry Felke-Morris http://terrymorris.net 15  Network Overview Network two or more computers connected together for the purpose of communicating and sharing resources Copyright © Terry Felke-Morris http://terrymorris.net 16  Networks LAN – Local Area Network ◦ Usually confined to a single building or group of buildings WAN – Wide Area Network ◦ Usually uses some form of public or commercial communications network to connect computers is widely dispersed geographical areas. Copyright © Terry Felke-Morris http://terrymorris.net 17  Internet Infrastructure Internet Backbone A high capacity communication link that carries data gathered from smaller links that interconnect with it. Maps of the Internet Backbone ◦ http://www.google.com/search?q=global+internet+backbone+map+images Copyright © Terry Felke-Morris http://terrymorris.net 18  The Client/Server Model Client/Server can describe a relationship between two computer programs – the "client" and the "server". Client ◦ requests some type of service (such as a file or database access) from the server. Server ◦ fulfills the request and transmits the results to the client over a network Copyright © Terry Felke-Morris http://terrymorris.net 19  The Internet Client/Server Model Client – Web Browser Server – Web Server Copyright © Terry Felke-Morris http://terrymorris.net 20  Web Client Connected to the Internet when needed Usually runs web browser (client) software (such as Internet Explorer or Firefox) Uses HTTP (Hypertext Transfer Protocol) Requests web pages from server Receives web pages and files from server Copyright © Terry Felke-Morris http://terrymorris.net 21  Web Server Continually connected to the Internet Runs web server software (such as Apache or Internet Information Server) Uses HTTP (Hypertext Transfer Protocol) Receives request for the web page Responds to request and transmits status code, web page, and associated files Copyright © Terry Felke-Morris http://terrymorris.net 22  MIME Type Multi-Purpose Internet Mail Extension ◦ a set of rules that allow multimedia documents to be exchanged among many different computer systems Copyright © Terry Felke-Morris http://terrymorris.net 23  Internet Protocols Protocols ◦ Rules that describe the methods used for clients and servers to communicate with each other over a network. ◦ There is no single protocol that makes the Internet and Web work. ◦ A number of protocols with specific functions are needed. Copyright © Terry Felke-Morris http://terrymorris.net 24  FTP - File Transfer Protocol A set of rules that allow files to be exchanged between computers on the Internet. Web developers commonly use FTP to transfer web page files from their computers to web servers. FTP is also used to download programs and files from other servers to individual computers. Copyright © Terry Felke-Morris http://terrymorris.net 25  E-mail Protocols Sending E-mail ◦ SMTP Simple Mail Transfer Protocol Receiving E-mail ◦ POP (POP3) Post Office Protocol ◦ IMAP Internet Mail Access Protocol Copyright © Terry Felke-Morris http://terrymorris.net 26  HTTP - Hypertext Transfer Protocol A set of rules for exchanging files such as text, graphic images, sound, video, and other multimedia files on the Web. Web browsers send HTTP requests for web pages and their associated files. Web servers send HTTP responses back to the web browsers. Copyright © Terry Felke-Morris http://terrymorris.net 27  TCP/IP Transmission Control Protocol/ Internet Protocol TCP/IP has been adopted as the official communication protocol of the Internet. TCP and IP have different functions that work together to ensure reliable communication over the Internet. Copyright © Terry Felke-Morris http://terrymorris.net 28  TCP Transmission Control Protocol Purpose is to ensure the integrity of communication Breaks files and messages into individual units called packets Copyright © Terry Felke-Morris http://terrymorris.net 29  IP Internet Protocol A set of rules that controls how data is sent between computers on the Internet. IP routes a packet to the correct destination address. The packet gets successively forwarded to the next closest router (a hardware device designed to move network traffic) until it reaches its destination. http://www.tracert.com/cgi-bin/trace.pl Copyright © Terry Felke-Morris http://terrymorris.net 30  IP Address Each device connected to the Internet has a unique numeric IP address. These addresses consist of a set of four groups of numbers, called octets. 173.194.116.72 will get you Google! An IP address may correspond to a domain name. Copyright © Terry Felke-Morris http://terrymorris.net 31  Domain Name Locates an organization or other entity on the Internet Domain Name System ◦ Divides the Internet into logical groups and understandable names ◦ Associates unique computer IP Addresses with the text-based domain names you type into a web browser ◦ Browser: http://google.com ◦ IP Address: 173.194.116.72 Copyright © Terry Felke-Morris http://terrymorris.net 32  Uniform Resource Identifier URI – Uniform Resource Identifier ◦ identifies a resource on the Internet URL – Uniform Resource Locator ◦ a type of URI which represents the network location of a resource such as a web page, a graphic file, or an MP3 file. Copyright © Terry Felke-Morris http://terrymorris.net 33  TLD Top-Level Domain Name A top-level domain (TLD) identifies the right-most part of the domain name. Examples of generic TLDs:.com,.org,.net,.mil,.gov,.edu,.int,.aero,.asia,.cat,.jobs,.name,.biz,.mobi,.museum,.info,.coop,.post,.pro,.tel,.travel Copyright © Terry Felke-Morris http://terrymorris.net 34  County Code TLDs Two character codes originally intended to indicate the geographical location (country) of the web site. In practice, it is fairly easy to obtain a domain name with a country code TLD that is not local to the registrant. Examples: ◦.tv,.ws,.au,.jp,.uk ◦ See http://www.iana.org/cctld/cctld-whois.htm Copyright © Terry Felke-Morris http://terrymorris.net 35  Domain Name System The Domain Name System (DNS) associates Domain Names with IP addresses. Web Domain Name Browser IP Address DNS Use TPC/IP to send HTTP Request Web Web Server Browser Use TCP/IP displays to send HTTP Responses web page with web page files & images Copyright © Terry Felke-Morris http://terrymorris.net 36  Markup Languages SGML – Standard Generalized Markup Language ◦ A standard for specifying a markup language or tag set HTML – Hypertext Markup Language ◦ The set of markup symbols or codes placed in a file intended for display on a web browser. Copyright © Terry Felke-Morris http://terrymorris.net 37  Markup Languages (2) XML – eXtensible Markup Language ◦ A text-based language designed to describe, deliver, and exchange structured information. ◦ It is not intended to replace HTML – it is intended to extend the power of HTML by separating data from presentation. Copyright © Terry Felke-Morris http://terrymorris.net 38  Markup Languages (3) XHTML – eXtensible Hypertext Markup Language ◦ Developed by the W3C as the reformulation of HTML 4.0 as an application of XML. ◦ It combines the formatting strengths of HTML 4.0 and the data structure and extensibility strengths of XML. Copyright © Terry Felke-Morris http://terrymorris.net 39  Markup Languages (4) HTML 5 ◦ The next version of HTML4 and XHTML ◦ http://www.w3.org/html/ Copyright © Terry Felke-Morris http://terrymorris.net 40  Checkpoint 1.2 Describe the components of the client/server model as applied to the Internet. Identify two protocols used on the Internet to convey information that use the Internet but do not use the Web. Explain the similarities and differences between a URL and a domain name. Copyright © Terry Felke-Morris http://terrymorris.net 41  Popular Uses of the Internet ◦ E-Commerce ◦ Mobile Access ◦ Blogs ◦ Wikis ◦ Social Networking ◦ RSS ◦ Podcasts ◦ Web 2.0 ◦ Cloud Computing Copyright © Terry Felke-Morris http://terrymorris.net 42  Summary This chapter provided a brief overview of Internet, Web, and introductory networking concepts. Copyright © Terry Felke-Morris http://terrymorris.net 43