Open knowledge
Knowledge that anyone can freely access, use, modify, and share, subject at most to requirements such as attribution or share-alike licensing.
Open definition: A standard describing when a work or resource is open for access, use, modification, and sharing. It sets the permissions that distinguish open knowledge from merely free-to-view material.
Open access: Free online availability of scholarly literature, often accompanied by rights that permit reuse. It is the best-known publishing practice for making research knowledge openly available.
Digital divide: Unequal access to digital technologies, connectivity, and the skills needed to use them. Open resources cannot produce equal access when infrastructure and skills remain uneven.
Paywall: A system that restricts access to digital content unless users pay or meet other conditions. It blocks the free access that open knowledge requires.
Creative Commons licenses: A family of public copyright licenses that let creators grant standardized permissions for sharing and reuse. These licenses commonly express the reuse permissions central to open knowledge.
Open educational resources: Teaching, learning, and research materials released under licenses that allow free use and adaptation. They make knowledge reusable in lessons, courses, and educational materials.
Knowledge commons: A shared resource of knowledge governed through collective rules and practices. Open knowledge can become a commons when communities sustain and govern shared resources.
All rights reserved: A copyright notice asserting that the copyright holder retains all rights not expressly granted. It contrasts with open licensing, which explicitly grants reuse permissions.
Public domain: Works not restricted by copyright, or whose copyright restrictions have expired or been waived. It permits reuse without the conditions that some open licenses retain.
Open science: A movement to make scientific research, data, methods, and outputs accessible and reusable. It extends openness across the research process, not only its published findings.