Chapter 13-Tools for the World Wide Web

Overview Web servers. Web browsers. Web page makers and site builders. Plug-ins and delivery vehicles. Beyond HTML.

Web Servers The functioning of the Web involves communication between a server computer and a client computer. A Web server is a computer that delivers a file when a client computer sends a request. Web servers vary in strength and capacity for a variety of platforms meeting the HTTP requirements.

Web Browsers Web browsers are applications that run on the client side (user’s PC) on the Internet. They provide an interactive graphical interface. This interface is used for searching, finding, and viewing text documents, sounds, and multimedia resources on the Web.

Web browsers differ in features, performance, and cost. Mozilla Firefox and Microsoft Internet Explorer are two of the most popular Web browsers. Web Browsers

Web Page Makers and Site Builders HTML documents are simple ASCII text files without any formatting. Active Server Pages, ColdFusion, or PHP are the programming environments needed for building dynamic sites. HTML translators are built into many word processing programs.

Web Page Makers and Site Builders HTML translators export a word-processed document with its text styles and layout converted into HTML tags. Many HTML editors and Web page-making applications offer to shortcut HTML learning curves and working effort.

Web Page Makers and Site Builders Dedicated editors are usually WYSIWYG (What You See Is What You Get) word processors.

Web Page Makers and Site Builders Adobe GoLive and Macromedia Dreamweaver MX are WYSIWYG HTML editors. GoLive allows a user to create and edit text pages, import images, and link to other documents.

Plug-ins and Delivery Vehicles Plug-ins allow end users to view and interact with new types of documents and images. Helper applications (or players) display or run files downloaded from the Internet.

Plug-ins and Delivery Vehicles Text. Images. Sound. Animation, video, and presentation.

Text Text and document plug-ins overcome the display limitations of HTML and Web browsers. Adobe Acrobat provides special fonts and graphic images embedded as data into the file.

Images Most browsers read only bitmapped JPEG, GIF, and PNG image files. Plug-ins that enable the viewing of vector formats (such as Flash) are useful. Vector graphics are device-independent. An image is displayed at the correct size and with colors supported by the computer.

Sound Digitized sound files in MP3, WAV, AIF, or AU formats may be sent and played on a user’s computer from Internet. MIDI sound files are more compact, but they depend upon the computer’s MIDI setup for quality.

Sound Speech files can be encoded into a token language that is a shorthand description of the speech components. Sound elements may also be embedded into projects made with various authoring tools. Some sounds can be multicast to allow multiple users to listen to the same data streams without duplication.

Animation, Video, and Presentation The most data-intense multimedia elements are video streams containing images and synchronized sound. Video streams are commonly packaged as Apple’s QuickTime, Microsoft’s Video for Windows (AVI), and as MPEG files. The trade-off between bandwidth and quality is ever present when designing, developing, and delivering animations or motion video for the Web.

Beyond HTML CGI (Common Gateway Interface) is a standard for interfacing external applications with information servers. Web-enabled 3-D environments promise compelling and interactive multimedia experiences.

Summary A Web server delivers a file when a client requests for it. Browsers are applications that run on a user’s PC to provide an interface for downloading and viewing documents and multimedia. Many HTML editors and Web page-making applications require less HTML skills and working effort. Plug-ins allow users to view and interact with new types of documents and images.