The idea that content should be freely available to use and distribute as people wish- without the restrictions from copyright and patents
Open Source
Where software's source code is made available for modification and improvement
Examples Include:
- LibreOffice
- GNU (Image Manipulation)
Open Hardware
Similar to Open Source Software, but instead refers to physical parts.
Examples Include:
- RepRap- A 3D printer that prints it's own parts for re-sale.
Open Content
Refers specifically to creative work that can be copied,edited and republished freely
Examples Include:
-Soundcloud- Music sharing service
- Anything licensed under Creative Commons
Open Data Licenses
Used to explain how the data of organisations can be used.
Example Licenses:
Reusable licenses that provide consistency and possess broader terms of use.
Used by governments and international organisations.
Open Data Initiatives
These are organised at different levels and possess overlapping jurisdictions.
Country Level:
Data featured is at a national level or just below. Often federated.
City and Subnational Levels:
Initiatives which contain data from a smaller/more focussed scope.
Useful Open Data
For Open Data to be considered useful it must meet certain conditions.
Developers need to harness the data to make new and valuable products & services.
Developers must integrate open data into existing products or services.
Closed Data
Closed data. is any form of data, ie 'digital data' for example, that is restricted for a reason. Pay walls along with encryption methods can be used, for issues concerning copyright and privacy, along with monetisation & political/commercial reasons.

Companies that support Open Data Include:
- Open Data Institute
- Open Knowledge Foundation
- ENGAGE platform
Examples of Closed Data include:
Examples of Closed Data
There are a few examples of Closed Data, they are often behind paywalls that stop the user from accessing data.
- The music service 'Tidal'
- Google Docs (Unless published)