Definition: 

"software designed to help people involved in a common task achieve their goals" (Wikipedia).  Includes tools to facilitate communication, conferencing, collaborative writing, sharing of resources, project management, and more.  Most of the tools featured in DiRT enable collaboration in some way.

Categories of Collaboration Tools:

• Annotation and Notetaking Tools
• Collaborative Authoring
• Data Collection
• Mashup
• Social Bookmarking
• Social Networking

Resources:

• Grant Bowman, "Collaborative Groupware Software"