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Providing Information On The Web 1 Brian Kelly UK Web Focus UKOLN University of Bath [email protected] http://www.ukoln.ac.uk/ Contents • Introduction • HTML - the File-Based Approach (bottom-up) • Basics of the language • Creating HTML pages • Managing a Web Site - the Site Approach (top-down) • Typical web site problems • Solutions • More than Simple Pages • Interactivity • Database integration • Technologies • HTML developments • Other developments 2 • Conclusions Aim Of Presentation To give an appreciation of the issues associated with providing information on the Web. UK Web Focus UK Web Focus: • National web coordination post for UK HE community • Based at UKOLN, University of Bath • Responsibilities include: – Technology watch – Information dissemination in variety of ways: – Workshops (national, regional) – Presentations at conferences and seminars – Online – Coordination activities – Representing JISC on W3C • Brian Kelly appointed on 1st November 1996 3 – Involved with web since January 1993 – Previously worked at University of Newcastle, Leeds, Liverpool, and Loughborough HTML - It's Easy HTML is a very simple language <TITLE>Hello World</TITLE> <H1>My First Page</H1> <IMG SRC="photo.gif">This is my <B>first</B> page on the web. <P> It's very easy! <A HREF="dog.html">Click here</A> to see my pet 4 HTML - Key Elements The HTML elements used to create simple HTML documents are very simple: <H1> - <H6> <P> <B>, <I> <IMG SRC="logo.gif"> <A HREF="intro.html"> Headings Paragraph (container) Formatting Inline images Hypertext link HTML Element <A HREF="http://www.w3.org/">The W3C</A> Start tag 5 End tag HTML - Even Simpler HTML authoring tools can make the task of creating HTML documents even simpler • No HTML tags to remember • Avoids typos • Many freely available • See http://www.stars.com/Vlib/ Authoring/HTML_Editors.html 6 HTML From Your Word Processor Users of word processor can create HTML documents without leaving their favourite application. Internet Assistant for Word Alternatively tools such as rtftohtml and HTML Transit can be used to convert from popular word processing formats 7 Conclusions To conclude: • HTML is very simple for simple documents containing text and graphics • HTML can be created by hand (using an editor such as Notepad) • HTML authoring tools, and word processing add-ons are readily available • Good news for authors of small numbers of pages (e.g. students) 8 Typical Web Site Problems 9 Many sites are facing problems of uncoordinated growth: • Large numbers of files to maintain • File and directory management • Out-of-date information • Inappropriate material • Unvalidated HTML • Cost of continual maintenance (e.g. to avoid oldfashioned looking pages) • Good design (attractive, quick to download, accessible, consistent, easily navigable) • Inappropriate hypertext writing style ("click here to return to University home page") Unvalidated HTML HTML which has not been validated can cause problems. In this example a quote (") is missing. This error will not be detected by looking at the page, only by following all links or using a validator. The talk on <EM>Providing Information on the Web</EM> will be given at <A HREF="http://www.herts.ac.uk/Libtech/libtech.htm>LibTech 97</A> 10 File / Directory Management Lack of file and directory naming conventions can cause problems: • Does http://www.ambridge.ac.uk/ conferences/LIS/ refer to this years conference or last? If it's this year's will it still exist in a year's time? • Is the URL http://www.ambridge.ac.uk/ conferences/lis/ , http://www.ambridge.ac.uk/ Conferences/LIS/ or http://www.ambridge.ac.uk/ Conferences/lis/ 11 • Who should have permissions to update the Conferences directory? Out-of-date Information On a large web site how is it possible to: • Find out-of-date information? • Identify ownership of resources? What Year? Are manual processes satisfactory? This existing web page refers to a conference held in April 1993! Note that no dates or information on ownership is provided. 12 Inappropriate Material Who is legally responsible for the following? • A student publishes pornography on his personal home page • A member of staff provides pointers to racists materials • A student makes defamatory remarks about her supervisor • A set of departmental web pages contain copyrighted images from Disney cartoons 13 Solutions Management Of Resources • Site/project management tools (e.g. Microsoft Front Page, NetObjects Fusion) enable pages to be managed in groups • Site management tools often allow meta information (e.g. review-by dates) to be provided Acceptable Use Policy • An Acceptable Use Policy (AUP) is essential for dealing with potential legal problems Planning Process • Need to sketch out directory structure (plan for future growth) 14 Directory Structures An example of a directory structure is shown root staff staff-list. html jbrown events Training manager maintains docs training admin about materials providing-info intro.html Jane Brown maintains Automatically generated files stored in separate directory iap-html providing.ppt NOTE Persistency of URLs is important. A reorganisation of your filestore will cause links to break 15 courses timetable .html timetable-96 .html Design Issues Issues: 16 • Attractive web pages can be important • But HTML defines structure • Images are (over) used for design purposes • This is slow, and causes accessibility problems • Proprietary HTML extensions but reduce accessibility • Technologies such as animation, frames, etc are controversial • Web design is a new skill (cf DTP in early 1980s) Egoless Design • Prepare a checklist of good and web design points • Produce a list of websites similar to your own • Ask your colleagues to view the sites and give comments on the checklist) • Produce a design specification based on the feedback Design Issues Think about hypertext writing style and content: • • • • 17 ACME Welcome to ACME's WWW site. Avoid "click here" Avoid "Back" Click here for product Which company? information. When was resource Click here for current updated? price lists. • What about Back to company home page copyright information, disclaimer, etc? More Than Static Pages - CGI CGI (Common Gateway Interface): • A standard for running software on the server • Creates a virtual document • Often used to link with web indexing software • Often used in conjunction with forms 18 Writing CGI software requires computing expertise Using a CGI program to search for clearing vacancies at the University of Hertfordshire More Than Static Pages - Java Java can be regarded as a programming environment for the web Used for: • Platform independent software development • Enhanced user interfaces But: • Steep learning curve (although tools arriving) 19 Database Integration Web / Database integration important: • Providing access to corporate databases • Providing consistent user interface Can be achieved by: • Batch conversion (e.g. using report option to include HTML tags) • Dynamic access • Various models for dynamic access: 20 – CGI gateways – ODBC, JDBC – Web server plugins Server-Side Management Server-side management techniques can be used to manage resources Software such as MS Active Server Pages, Netscape SuiteTools, PHP/FI, is available. <If useragent=netscape1.1 then else if useragent= …> <P>This resource is copyright ... Adding code / text to static HTML resource: • complex • difficult to maintain <#If useragent=netscape1.1 then else if useragent= …> <#include copyright-1.txt> 21 Server side management tools: • HTML resource clean • easier to maintain HTML Developments End user control over layout, better printing, ... Why: Increased functionality Barriers: Lack of standards How: CSS, HTML 4.0 (Cougar) Familiarisation: IE 4, Netscape 4, HTML 4.0 proposal 22 HTML 4.0 and Related Work • Forms: Improved forms • Printing: Better control over printing • CSS: Stylesheets • Layout: Absolute positioning of HTML elements, layering, etc • Document Object Model (DOM): APIs (application program interface) for HTML/CSS elements. Provides a programming interface for HTML (hooks for Javascript, etc.) <SCRIPT LANGUAGE="JavaScript"> <!-- Hide this from JavaScript-challenged browsers var FirstSlide = 1;var LastSlide = 17; var CurrentSlide = FirstSlide;var ImageWidth = 708 - 8; var ImageHeight = 520; var CurImageWidth = ImageWidth; var CurImageHeight = ImageHeight; /* This function concerts numbers to strings */ <HTML><BODY > <A HREF="JavaScript:parent. function CvtNtoS(iNum) ItemClicked(1, 0)"> An Introduction to {return ("" + iNum);} /* This function prefixes strings with the correct # of 0's */Metadata </A><BR> <A HREF="JavaScript:parent. function ZeroFill(iNum, iDigits) ItemClicked(2, 0)"> UK Web Focus { var sNum = CvtNtoS(iNum); </A><BR><A HREF="JavaScript: while (sNum.length < iDigits) parent.ItemClicked(3, 0)"> Early Days sNum = "0" + sNum; of the Web (1) </A><br> return sNum;} HTML><BODY > /* this function handles the setting the navigation buttons. <base target="_top"> The name of navigation control is used here so change it if it is renamed */ <A HREF="JavaScript: function ItemClicked(iIndex, iNoteOnly) parent.OutlineExpand(0)"><IMG {var sIndex = ZeroFill(iIndex, 3); SRC="collapse.gif" BORDER=0 var sNoteHref = "note" + sIndex + ".htm"; ALT="Collapse"></A> var sSlideImage = "img" + sIndex + ".htm"; <A HREF="JavaScript: if (!iNoteOnly) // not active X, update image and nav btns parent.OutlineExpand(1)"><IMG frames["SlideImage"].location.href = sSlideImage; SRC="expand.gif" BORDER=0 frames["Notes"].location.href = sNoteHref; ALT="Expand"></A> CurrentSlide = iIndex;} <STRONG>Demise of Tags</STRONG> Demise of text editor for authoring Why: HTML will be too complex Barriers: Inertia. Too many tools! How: Recommendations on authoring tools Familiarisation: Front Page, Netobjects Fusion, ... 23 Style Sheets HTML philosophy: • HTML describes document structure • Document appearance defined elsewhere Netscape / Microsoft wars resulted in: 24 • Breakdown of this philosophy • Proprietary tags • Increases in network traffic • Lacked flexibility Increasing Use Of Java 25 Expect to see increasing use of Java: Why: Provide extra functionality on client; Minimise support load for desktop applications Barriers: Performance concerns (real and imaginary - cf XMosaic) How: Standard web browser Z39.50 clients are being Familiarisation: http://www.gamelan developed using Java .com/ A Customisable Web End user choice of preferred formats (HTML or PDF, GIF or PNG), features (frames or tables), languages, etc. Why: Choice for the end user, deployment of new features Barriers: Lack of standards, misuse of HTML How: TCN, Cookies Familiarisation: http://tips.iworld.com/ 26 Replace this with use of cookies or transparent content negotiation Check List (1) Business Case Clarify your need for a web site: – – – – Everyone else has one It's fashionable Reduce costs (will it?) Improve quality of access to information Costings – Hardware, software and network costs – Staffing costs Information Flow – How will web service integrate with existing information systems? – Who "owns" the information? 27 Check List (2) Technologies • Choice of server architecture • Authoring models (file-based v. project/site based) • Integration of existing systems (e.g. databases) • (Appropriate) Use of new technologies (e.g. Java, HTML 4.0, Style Sheets, etc.) Guidelines • Formulation of acceptable use policies • Procedures for misuse • Guidelines for information providers 28 Who Does The Work? The term webmaster is a misnomer - a web team is needed for large web sites Web Policy Group • Management group • Deals with resources and policies 29 System Administrator • Installs and maintains server software • Deals with security Web designer Information specialist • Knowledge of information flow procedures • Defines guidelines Software support • Design skills • Knowledge of web design issues Content provider(s) • Supports desktop software (e.g. authoring tools) • May be computing service • Everybody? Conclusions • Creating Web pages is easy for "Joe Homepage" • Creating and maintaining a large web site can be expensive • Several models for providing web sites can be used • A variety of technologies can be used • Careful planning is essential to avoid escalating costs 30