Lead Design: Sam Reid (Energy Skate Park) & Noah Podolefsky (Energy Skate Park Basics)
Software Development: Sam Reid
Design Team: Wendy Adams, Michael Dubson, Trish Loeblein, Emily Moore, Ariel Paul, Kathy Perkins & Carl Wieman
Interviews: Danielle Harlow, Noah Podolefsky & Ariel Paul
PhET SOFTWARE AGREEMENT
University of Colorado
In this document:
I. Software License Options
A. Option A: Creative Commons - Attribution (executables only)
B. Option B: Creative Commons - GNU GPL (executables and source code).
E. Third Party Software Credits
F. Alternative Licensing Options
A. Commitment to Individual Privacy
B. Information Collected
C. Information Security
D. Information Sharing
E. Colorado Open Records Act
F. Setting User Preferences
IV. Contact Us
V. Appendix A: Creative Commons Attribution 3.0 License (full text)
VI. Appendix B: GNU General Public License (full text)
I. SOFTWARE LICENSE OPTIONS
The PhET Interactive Simulations Project at the University of Colorado (PhET) distributes these simulations under the Creative Commons-Attribution 3.0 license and the Creative Commons GNU General Public License as detailed below. The user is responsible for choosing which of
the two licensing options will govern their use of these simulations.
Both license options require attributing the work to:
PhET Interactive Simulations
University of Colorado http://phet.colorado.edu.
If your use includes redistribution of the simulations, please let us know! This type of information is very useful when writing proposals for future funding.
Please consider contributing a tax-deductible donation to PhET to help keep the project going.
The full text of the Creative Commons Attribution license appears in Section V Appendix A.
What does this mean?
The interactive simulations developed by PhET Interactive Simulations (with exceptions listed above) may be freely used and/or redistributed by third parties (e.g. students, educators, school districts, museums, publishers, vendors, etc.). Non-commercial or commercial use is
allowed. All uses require attribution of the work as described in the ATTRIBUTION section.
Parties wishing to modify the source code must use Option B.
B. OPTION B: CREATIVE COMMONS - GNU GENERAL PUBLIC LICENSE
The full text of the GNU General Public License appears in Section VI Appendix B.
What does this mean?
The interactive simulations developed by PhET Interactive Simulations may be freely used and/or redistributed by third parties (e.g. students, educators, school districts, museums, publishers, vendors, etc.). Non-commercial or commercial use is allowed. All uses require
attribution of the work as described in the ATTRIBUTION section.
In addition, the source code for all PhET simulations is available for use and/or modification. For directions about how to access the source code, go to: http://phet.colorado.edu/about/source-code.php. Anyone can
have access to the source code and make modifications. The source code for any changes someone makes to the software must, in turn, be made publicly available by the party that makes the changes.
Both license options require attributing the work to:
PhET Interactive Simulations
University of Colorado http://phet.colorado.edu
PhET needs ongoing donations and grant funding in order to support the project, continue the development of new simulations, and maintain existing simulations.
PhET's simulations use third-party software. A complete list of third-party software used, the developers, and the associated licenses is available from within each simulation. In Java, from the Help -> About menu, choose the Credits button. In Flash, open the dialog using
the About button, and then choose the credits button.
The University of Colorado and the PhET Project are committed to the protection of individual privacy, and ensuring the confidentiality of information provided by its employees, students, visitors, and resource users.
B. INFORMATION COLLECTED
In order to document the amount of use of PhET simulations and to provide the best services to our users, PhET collects a minimal amount of non-personally identifying information upon each simulation start-up (e.g. sim version, operating system, java version, ...).
When the simulation is launched online from http://phet.colorado.edu, information is collected via standard website statistics services.
When the simulation is launched from another source (e.g. a downloaded simulation file), a small message is sent to PhET as the simulation starts up. You can disable sending this information (see USER PREFERENCES below).
A complete list of the information sent to PhET is available in the simulations. For Java simulations, go to Files->Preferences, select the Privacy tab, and click on the "information" link. For Flash simulations, go to the Preferences button and click on the "information"
link in the Privacy section.
C. INFORMATION SECURITY
The PhET Project has in place appropriate security measures to protect against the unauthorized use or access of its data. Such measures include internal review of data collection, storage, and processing practices and security measures, as well as physical security measures
to guard against unauthorized access to systems where data is stored.
D. INFORMATION SHARING
Access to information collected through the use of PhET simulations is limited to those employees, contractors, and agents who need to know that information in order to operate, develop, or improve our services. The PhET Project may report a summary of this information (in
aggregate) to other organizations and individuals for grant reporting purposes, or in published articles to document PhET's wide-spread use. No personally-identifying information is collected nor distributed. The PhET Project requires third parties to whom it discloses
information to protect the information in accordance with this policy and applicable law. In addition, the PhET Project may disclose information to third parties when such disclosure is required or permitted by law.
E. COLORADO OPEN RECORDS ACT
The University of Colorado and the PhET project are subject to the Colorado Open Records Act, C.R.S. § 24-72-101 et seq. The Colorado Open Records Act requires that all records maintained by the University and the PhET Project be available for public inspection
except as otherwise provided by law. Non-personal identifying information collected by the PhET Project may be subject to public inspection and copying unless protected by state or federal law.
F. SETTING USER PREFERENCES
For simulations launched online from http://phet.colorado.edu, no preferences options are available because the simulation sends no start-up message to PhET.
When launching PhET simulations from any other location (e.g. a downloaded offline version), users may choose to disable the feature which sends the information message to the PhET Project.
Instructions for Java simulations: From the File->Preferences menu, choose the Privacy tab and uncheck the box in front of "Allow sending of information to PhET." Users will still be able to receive notices of updates, but in this case, no information is sent to the PhET
Project. To disallow updates, uncheck 'Automatically check for updates' in the Updates tab.
Instructions for Flash simulations: Open the dialog using the Preferences button. Uncheck the box in front of "Allow sending of information to PhET" in the Privacy section. Users will still be able to receive notices of updates, but in this case, no information is sent to the
PhET Project. To disallow updates, uncheck 'Automatically check for updates' in the Updates section.
This software and the information contained therein is provided as a public service, with the understanding that neither the University of Colorado nor the PhET project makes any warranties, either express or implied, concerning the accuracy, completeness, reliability, or
suitability of this software and information.
By using this software, you assume all risks associated with such use, including but not limited to the risk of any damage to your computer, software, or data. In no event shall the University or the PhET project be liable for any direct, indirect, punitive, special,
incidental, or consequential damages (including, without limitation, lost revenues or profits or lost or damaged data) arising from your use of this software.
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VI. APPENDIX B: GNU GENERAL PUBLIC LICENSE (full text)
GNU GENERAL PUBLIC LICENSE
Version 2, June 1991
Copyright (C) 1989, 1991 Free Software Foundation, Inc.
51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is not allowed.
The licenses for most software are designed to take away your freedom to share and change it. By contrast, the GNU General Public License is intended to guarantee your freedom to share and change free software--to make sure the software is free for all its users. This General
Public License applies to most of the Free Software Foundation's software and to any other program whose authors commit to using it. (Some other Free Software Foundation software is covered by the GNU Lesser General Public License instead.) You can apply it to your programs,
When we speak of free software, we are referring to freedom, not price. Our General Public Licenses are designed to make sure that you have the freedom to distribute copies of free software (and charge for this service if you wish), that you receive source code or can get it
if you want it, that you can change the software or use pieces of it in new free programs; and that you know you can do these things.
To protect your rights, we need to make restrictions that forbid anyone to deny you these rights or to ask you to surrender the rights. These restrictions translate to certain responsibilities for you if you distribute copies of the software, or if you modify it.
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We protect your rights with two steps: (1) copyright the software, and (2) offer you this license which gives you legal permission to copy, distribute and/or modify the software.
Also, for each author's protection and ours, we want to make certain that everyone understands that there is no warranty for this free software. If the software is modified by someone else and passed on, we want its recipients to know that what they have is not the original,
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Finally, any free program is threatened constantly by software patents. We wish to avoid the danger that redistributors of a free program will individually obtain patent licenses, in effect making the program proprietary. To prevent this, we have made it clear that any patent
must be licensed for everyone's free use or not licensed at all.
The precise terms and conditions for copying, distribution and modification follow.
GNU GENERAL PUBLIC LICENSE TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
0. This License applies to any program or other work which contains a notice placed by the copyright holder saying it may be distributed under the terms of this General Public License. The "Program", below, refers to any such program or work, and a "work based on the Program"
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Activities other than copying, distribution and modification are not covered by this License; they are outside its scope. The act of running the Program is not restricted, and the output from the Program is covered only if its contents constitute a work based on the Program
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12. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL
DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS), EVEN IF SUCH HOLDER OR
OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
END OF TERMS AND CONDITIONS
How to Apply These Terms to Your New Programs
If you develop a new program, and you want it to be of the greatest possible use to the public, the best way to achieve this is to make it free software which everyone can redistribute and change under these terms.
To do so, attach the following notices to the program. It is safest to attach them to the start of each source file to most effectively convey the exclusion of warranty; and each file should have at least the "copyright" line and a pointer to where the full notice is found.
"one line to give the program's name and a brief idea of what it does.
Copyright (C) -year- -name of author-
This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA."
Also add information on how to contact you by electronic and paper mail.
If the program is interactive, make it output a short notice like this
when it starts in an interactive mode:
"Gnomovision version 69, Copyright (C) year name of author
Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type 'show w'.
This is free software, and you are welcome to redistribute it
under certain conditions; type 'show c' for details."
The hypothetical commands 'show w' and 'show c' should show the appropriate parts of the General Public License. Of course, the commands you use may be called something other than 'show w' and 'show c'; they could even be mouse-clicks or menu items--whatever suits your
You should also get your employer (if you work as a programmer) or your school, if any, to sign a "copyright disclaimer" for the program, if necessary. Here is a sample; alter the names:
"Yoyodyne, Inc., hereby disclaims all copyright interest in the program `Gnomovision' (which makes passes at compilers) written by James Hacker.
signature of Ty Coon, 1 April 1989
Ty Coon, President of Vice"
This General Public License does not permit incorporating your program into proprietary programs. If your program is a subroutine library, you may consider it more useful to permit linking proprietary applications with the library. If this is what you want to do, use the GNU
Public License instead of this License.