Architect Christopher Alexander introduced the concept of pattern language in his 1979 book The Timeless Way of Building, describing a pattern as, “a three part rule, which expresses a relation between a certain context, a problem, and a solution”.

In architecture and planning, patterns provide a repeatable approach to the common aspects of a variety of locations, climates, planning considerations, and uses.

In online content strategy and community-building, patterns provide the same kind of repeatable approach and definition to common roles and techniques, such as: the person who fixes typos and formatting (Gardener), the templates that jump-start participation (Scaffold), and the person who encourages others to use the tool (Champion).

Other Pattern Libraries

• Designing Interfaces: Patterns for Effective Interaction Design
• List of Pattern Repositories – InfoDesign
• UX Design Terminology – Konigi