Open source software
This is essentially the same as free software ("free as in freedom") but the different terms reflect a different philosophy and emphasis.
 Open source and development issues
It is highly advisable that Free Culture and Copyleft licenses such as the Creative Commons Attribution Share Alike (CC-BY-SA) license be considered for all written material and software related to development.
This allows free use and distribution of the material (free as in freedom). Free Culture licenses allow anyone to take anything published under that license and adapt it anyway they want and resell it and charge whatever they want for it. Copyleft licenses also allow this but the require the the reseller give their customers the same rights to copy and resell the adapted work, just like the original work. This does limit the profit that a reseller can make. If I reprint Appropedia as a book I can sell it to people who want the information in that form but if I try to charge a ot for it then someone else will bring out a cheaper version. Competition keeps the price dowm.
A relevant example is the clay pot filter, which was deliberately not patented, to avoid restrictions on people wanting to use the design. Though thought must also be given to ensuring that no one else will patent it. If the design and use of the invention is clearly documented, that will prevent others from being able to claim it as their invention.
See The Green Road to Open Access: A Leveraged Transition by Stevan Harnad for a discussion of the positive access of open access on the pace of progress in research. "Cumulative research impact keeps being lost daily, weekly, yearly, because of access-denial to would-be users whose universities cannot afford the access-tolls." Not that this is particularly relevant to those in the "majority world" (and the less advantaged in wealthy countries) who cannot afford journal and database subscriptions.
 Open source software
- The freedom to run the program, for any purpose (freedom 0).
- The freedom to study how the program works, and change it to make it do what you wish (freedom 1). Access to the source code is a precondition for this.
- The freedom to redistribute copies so you can help your neighbor (freedom 2).
- The freedom to improve the program, and release your improvements (and modified versions in general) to the public, so that the whole community benefits (freedom 3). Access to the source code is a precondition for this.
There are many examples, including:
- Linux operating system
- OpenOffice Office Suite
- See Wikipedia:Open-source software for more.
- Project Gutenberg - are there texts here relevant to development? (Educational texts, texts for use by English learners?)
- English language learning and teaching: Wikibooks would be the ideal place to develop open source resources for this. It has some material already, that needs organising and developing. See Wikibooks:English as an Additional Language, and some more of these pages here. See also a major ESL discussion site, Dave's ESL Cafe, where there are many keen teachers who might be keen to join a collaboration.