Tagging : people-powered metadata for the social web / Gene Smith.

What Is tagging?
How tagging works
Why tagging matters
Summary
The value of tagging
What tags can do for you
Return on experience: five motivations for tagging
Return on investment: seven business benefits
Summary
Tagging system architecture
Users, resources, and tags: exploring our three-part model of tagging
Tagging in practice: examples from the real world
Summary
Tags, metadata, and classification systems
Metadata for the masses
Taxonomies and controlled vocabularies
Facets
Folksonomies
Tags in the metadata ecosystem
Summary
Navigation and visualization
Tag clouds
Navigating tags
Geotagging
Summary
Interfaces
Patterns in tagging interfaces
Tag entry
Suggestions
Tag management
Summary
Technical design
Data models
Tag clouds
Freetag
Summary
Appendix A. Case study: social bookmarking
Tagging evolution: from Muxway to Del.icio.us
How social bookmarking works
Summary
Appendix B. Case study: media sharing
How media sharing works
Summary
Appendix C. Case study: personal information management
Tagging for PIM
Summary.