Terms in plain language
Use the public puzzles, guides, and tools for learning. Do not harm the service or present the site's original work as your own.
Main use rules
- Personal and educational use: public pages may be used for study and teaching.
- High-stakes decisions: educational frameworks do not replace qualified advice.
- Original work: full collections and mirrored services need written permission.
Using the site
You may use the public puzzles, guides, and tools for personal and educational purposes. Do not interfere with the service, bypass access controls, scrape at a rate that harms availability, or present our editorial work as your own.
No professional advice
Problem-solving frameworks are educational. They are not legal, medical, financial, safety, or psychological advice. High-stakes decisions require qualified help and evidence appropriate to the situation.
Accuracy and availability
We work to keep explanations accurate and tools available, but puzzles can contain ambiguity and software can fail. Use the contact page to report an issue so it can be checked under the editorial quality policy. The service is provided without a guarantee of uninterrupted availability.
Intellectual property
Original text, challenge collections, illustrations, and software are protected by applicable law. Brief quotation with attribution is welcome. Republishing complete collections or operating a mirrored service requires written permission. The privacy policy explains how messages and standard service data are handled.