It's Gimp running on GNU/Linux Ubuntu, they are all free software and there is no copyright on it. I took this screenshot by myself.
Date
23 April 2006 (original upload date)
Source
No machine-readable source provided. Own work assumed (based on copyright claims).
Author
No machine-readable author provided. Alejo2083 assumed (based on copyright claims).
Licensing
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Free software license:
This work 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 3 of the License, or any later version. This work 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 version 3 of the GNU General Public License for more details.GNU General Public License v3GPLv3http://www.gnu.org/licenses/gpl-3.0.htmltrue
Note: if the screenshot shows any work that is not a direct result of the program code itself, such as a text or graphics that are not part of the program, the license for that work must be indicated separately.
A screenshot for use in the tutorial Commons:Cleaning up interference with Fourier analysis. It's Gimp running on GNU/Linux Ubuntu, they are all free software and there is no copyright on it. I took this screenshot by myself.