Licences
The books, their figures and data, the calculators and the website code may be shared and adapted for any purpose, provided that they are credited. The simulation tools are free to use, but their code is not open: they may not be modified or redistributed. This page lists the licence of each type of material, gives the tools' licence in full and explains how to give credit.
Licences by type of material
| Material | Licence |
|---|---|
| Text, figures, animations and data in the books and on the website | Creative Commons Attribution 4.0 (CC BY 4.0) |
| Calculators, interactive elements and website code | MIT licence |
| Simulation tools | The OpenNAOE Tool Licence 1.0 for the tools' own code: free to use; not to be modified or redistributed. Third-party components keep their own licences, listed in each tool's notices; the parts of Hull Resistance CFD derived from OpenFOAM are under GPL-3.0-or-later, and their source is provided with them. |
| Third-party material, such as a public-domain photograph | The licence of the original, shown with its credit where the material is used. |
| Typefaces (Archivo, IBM Plex Sans, IBM Plex Mono, Source Serif 4) | SIL Open Font License 1.1, as published by their designers. |
The OpenNAOE Tool Licence
Each simulation tool is released under this licence, which the tool itself states on its About page (Hull Resistance CFD, in its installation package and at the foot of its interface).
OpenNAOE Tool Licence, version 1.0
Copyright (c) 2026 Mohammed Abdul Hannan. All rights reserved.
- Use. You may use this tool free of charge, for any purpose, and make copies of it for your own use. A school, university or other organization may also install it on the computers it manages, for the people who use them. It is intended for learning, teaching and early design exploration, not for commercial engineering work: if you use it for other work, including consultancy, or rely on its results, you do so entirely at your own risk.
- Your inputs and results. This licence claims no rights in the inputs you give the tool or in the results it produces for you, and places no conditions on how you use, publish or share them.
- Restrictions. You may not modify the tool, use any part of its code in other software, or distribute the tool or any part of its code, modified or not. Preparing your own inputs, including by editing copies of the example and configuration files the tool provides, is use, not modification. Others can obtain the tool from opennaoe.org.
- Other licences. Third-party components are under their own licences, and any part of the tool that a third-party licence requires to be licensed under it is under that licence; the tool's notices list them. Those licences, not this one, govern those parts, and nothing in this licence restricts what they permit.
- No warranty; no liability. The tool is provided "as is", without warranty of any kind, express or implied, including any warranty of accuracy or of fitness for a particular purpose. Its scope and limits are stated in the tool. The author is not liable for any claim, damage or other liability arising from the tool, its use, its results or any decision made with them. These exclusions apply to the extent permitted by applicable law.
- Name and logo. This licence gives no right to use the OpenNAOE name or logo.
How to give credit
A credit names the work, the author, the source and the licence. For example, for a figure:
Example credit
Figure 4.3 from M. A. Hannan, Hydrostatics & Stability, OpenNAOE, version 1.0, https://doi.org/10.5281/zenodo.23816840. CC BY 4.0.
If the material has been modified, this should be stated (for example, "adapted from ..."). To cite a book, chapter or tool in a publication, see How to cite.
Licence information in the files
Each source file of the books and the website states its licence in machine-readable form, following the REUSE specification, so that the terms of reuse can be checked before the file is copied. Each simulation tool states its licence, and the notices of its third-party components, on its About page; Hull Resistance CFD states them in its installation package and at the foot of its interface.