What is a Wiki?
- a technology for collaborative creation of internet and intranet pages
- Wiki-Wiki is hawaiian and means fast 
Principles
- Fast - fast editing, communicating and easy to learn 
- Open - everybody may read and edit everything 
- Uncomplicated - everything works in a standard browser 
- Easy - no HTML knowledge necessary, simply formatted text 
- Simple - Content over Form (content counts, not the super-pretty appearance) 
- Secure - every change is archived, nothing gets lost 
- Interlinked - Links between pages are easy to make 
- Flexible - Personal Information Management, Knowledgebases, Brainstorming
- Collaboration, Coordination and Communication platform
- Creating documentation and slide shows   
- etc...
 
For details see HelpForBeginners.
