web technology and terminology

Web Technology & Terminology

Bruce Clary, McPherson College, McPherson, Kansas

CM350 WEB DESIGN FOR EFFECTIVE COMMUNICATION

Internet

• International network of computers used to share data.

• Includes e-mail, bulletin boards, IM, newsgroups, databases, streaming audio and video–almost all of which can now be delivered through the WWW.


World Wide Web


World Wide Web

• The graphical interface that uses the Internet to share information.


World Wide Web

• The graphical interface that uses the Internet to share information.

• The WWW cannot exist without the Internet. The Internet can and does exist without the Web.


ProtocolsSets of rules that allow data to be shared via the Internet

• HTTP: HyperText Transfer Protocol• FTP: File Transfer Protocol


HTTPHyperText Transfer Protocol

The protocol, or rules, that move Web pages across the Internet and that link pages together

• One way transfer, server to browser• Stateless (which means no copy of the transfer is

saved on the server side)

FTPFile Transfer Protocol

The rules that move digital files across the Internet• Two way• Copies of transfers on both server and client sides

IPInternet Protocol

IP addresses are unique numbers that identify specific computers connected to the Internet.


• The rules that identify specific files available on the Internet

• The address beginning with the transfer protocol http:// in a browser address bar

• See pg. 22 in Robbins for parts of a URL address

URLUniform Resource Locator


http://bulldog.mcpherson.edu/~shordeo/ex_4-5.html



Protocol




Protocol Host




Protocol DomainHost




Protocol

Site Name

DomainHost




Protocol

Site Name

DirectoryDomainHost




Protocol

Site Name

FileDirectoryDomainHost




Protocol

PathSite Name

FileDirectoryDomainHost




DNSDomain Name System

Connecting to computers and Web sites through the Internet would be far more laborious and error-prone if it had to be done with IP addresses—e.g., 10.0.1.197). The DNS translates domain names (e.g., www.mcpherson.edu) that have meaning into an IP address.


• See pg. 31 in Robbins for illustration of HTTP requests and responses

How it all works


Why are browsers different?

• Independently developed• Document Object Model (DOM) support varies• Each uses independent JavaScript engines• Multiple rendering engines drive layout &

appearance


Multiple rendering engines

Trident Blink Gecko Web-Kit


Browser consistency driven by Web Standards



• In 1990s, market share drives browser development



• In 1990s, market share drives browser development• Development of open-source browsers such as

Firefox and Opera in 2000s finally get attention of commercial browser developers


Other ubiquitous Web technologies



• JavaScript: A client-side scripting language (which means end-users can turn it off, disabling any parts of your Web page dependent upon scripting)




• jQuery: A JavaScript library that can be called with just a few lines of code in your HTML pages





• PHP: Hypertext Preprocessor (originally, Personal Home Page





• PHP: Hypertext Preprocessor (originally, Personal Home Page

• CMS: Content Management System (e.g., Wordpress, Bulldog Connect, even Facebook)


More essential Web technologies



• MySQL: Structured Query LanguageThe preceding “My” indicates that MySQL is Open Source and free for anyone to use




• XML: eXtensible Markup Language




• XML: eXtensible Markup Language• AJAX: Asynchronous JavaScript and XML


web technology and terminology

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