Effective 9 October 2026.
About the site
raycat.org is an educational project: interactive explanations of how things work. We work hard to keep the models honest, but this is popular science, not a textbook or a manual. Where a model is simplified, we say so.
Copyright
The texts, figures, code of the interactive models, narration and videos belong to the Raycat project. You may link to them and quote short passages with credit and a link to raycat.org. To use the materials in other ways, for example in a course, a museum or an app, write to us: we are usually glad to help.
The Unbounded, Literata and JetBrains Mono typefaces are distributed under the SIL Open Font License, and the three.js library under the MIT License.
Generated material
Some cover images are generated by AI, and the narration voice is synthetic. We say so next to such material.
No warranty
The materials are provided “as is”. We fix mistakes as soon as we learn about them, but we cannot guarantee there are none, and we are not liable for decisions based on the materials on this site.
Other sites
The site links to other services and embeds YouTube videos. Those services are responsible for their own operation and rules.
Changes
We may update these terms; the new version will appear on this page with a new date.