1 An Introduction to Metadata Brian Kelly UK Web Focus UKOLN University of Bath BA2 7AY

2 UK Web Focus UK Web Focus is: A JISC funded initiative Based at UKOLN, University of Bath Involved in various WWW activities: –Technology watch –Information dissemination throughout UK HE community –Coordination of WWW activities –Represents JISC on W3C Brian Kelly appointed as UK Web Focus on 1st November 1996

3 Early Days of the Web (1) In the early days of the Web (1994): The number of information providers was small The Web was simple (HTML) Information providers could cope

4 Early Days of the Web (2) Searching resulted in manageable numbers of hits A search for Leeds using the WWW Worm (indexed WWW in 1994) results in 17 hits

5 The Web Today (1) Today: Managing files difficult The Web is slow Web is more difficult to understand (HTML, mobile code, Java, ActiveX, VRML, …)

6 The Web Today (2) The Web today: Searching results in too many low-quality hits “Index spamming” causes problems

7 What Is Metadata? Metadata is: “Data about data” For a book, the author’s name, publisher, ISBN, date of publication, … are metadata For a Web resource metadata can include: –Author (text resource) / Painter (image of painting) / Composer (music resource) –Keywords –Much more Metadata can be used for: –Resource discovery –Information management

8 Institutional Metadata Queen’s University Belfast have produced institutional recommendations for metadata: GeneratorSoftware used to generate document SubjectHistory, Psychology, … AuthorAuthor of the document KeywordsChosen keywords to aid searches ObjectTypeLecture Notes, Mail Archive, Exam Paper… … Implemented using tag: See webmasters/metatags.html

9 Need for Standards Institutional metadata: Useful for site management Less useful for resource discovery Agreement on metadata syntax and vocabulary needed: Dublin Core Meeting held at Dublin, Ohio to agree on a core set on metadata attributes for Internet resources

10 Dublin Core Dublin Core defines a set of core metadata attributes: Title Subject and Keywords DescriptorCreator or Author Publisher Contributor DateResource Type FormatResource Identifier RelationSource LanguageCoverage Rights Management Title Subject and Keywords DescriptorCreator or Author Publisher Contributor DateResource Type FormatResource Identifier RelationSource LanguageCoverage Rights Management See Please note that the attributes may change. See the online information for latest details

11 Other Solutions (1) Apple’s Hot Sauce / Meta-Content Format (MCF) See text/mcf.htm See review at tb-issues/TidBITS-355.html

12 Other Solutions (2) RDM (Netscape) –Based on Harvest –Submitted to W3C (see pub/WWW/TR/NOTE-rdm.html ) Sitemap (Microsoft) –To provide an auxiliary UI navigation resource for working in web/hypertext spaces. –Status uncertain. Lycos –

13 PICS PICS (Platform for Internet Content Selection): A technical solution to pornography problem Widely used in US At PICS WG meeting (13/14 Jan 97): Recognition that PICS is a metadata format Proposal to use PICS as general metadata language Proposal to use PICS to store digital signatures Discussions about providing multiple links using PICS

14 Managing Metadata Information Management Problems Long-standing information providers often have 100s of HTML files to maintain Website administrators can have thousands (millions?) of files to maintain How is the Website maintained when: –A new HTML facility is to be used? –A new look-and-feel is needed? –A standard footer is to be included? Information Meta-Management Problems

15 Site Management Tools NetObjects Fusion is an example of a site design tool These tools enable: A consistent look and feel to be applied to a Website Changes to be made easily We can expect to see such tools incorporating site meta-management

16 What Should I Do Now? What should you do now for your Website? Measure size of your Website and estimate future growth Define your site metadata needs Define metadata vocabulary Define metadata maintenance mechanism (procedures and tools) Keep informed of metadata developments

17 Further Information Metadata for the Masses issue5/metadata-masses/ Archive of meta2 Mailing list /meta2/ PICS