# Hidden Radius

> A standalone U.S. search-intelligence company and knowledge centre explaining the systems beneath modern discovery.

## Canonical website
- https://hiddenradius.com/

## Core models
- [The Hidden Radius Model](https://hiddenradius.com/hidden-radius-model/)
- [The Search Discovery Stack](https://hiddenradius.com/discovery-stack/)
- [Search Outcomes](https://hiddenradius.com/search-outcomes/)
- [How the Terms Work Together](https://hiddenradius.com/terms-work-together/)
- [Comparison Matrix](https://hiddenradius.com/comparison-matrix/)

## Core disciplines and systems
- [SEO](https://hiddenradius.com/seo/)
- [GEO](https://hiddenradius.com/geo/)
- [AEO](https://hiddenradius.com/aeo/)
- [AIO](https://hiddenradius.com/aio/)
- [LLMs](https://hiddenradius.com/llms/)
- [RAG](https://hiddenradius.com/rag/)
- [REG](https://hiddenradius.com/reg/)
- [Entity Recognition](https://hiddenradius.com/entity-recognition/)
- [Information Retrieval](https://hiddenradius.com/information-retrieval/)

## Infrastructure and reliability
- [Crawling and Indexing](https://hiddenradius.com/crawling-indexing/)
- [Structured Data](https://hiddenradius.com/structured-data/)
- [Knowledge Graphs](https://hiddenradius.com/knowledge-graphs/)
- [Agents and Tool Use](https://hiddenradius.com/agents-tool-use/)
- [Reliability and Source Quality](https://hiddenradius.com/reliability-source-quality/)

## Research library
- [Research Library](https://hiddenradius.com/research-library/)
- [NIST](https://hiddenradius.com/nist/)
- [Stanford AI Index](https://hiddenradius.com/stanford-ai-index/)
- [OECD](https://hiddenradius.com/oecd/)
- [Google Search Central](https://hiddenradius.com/google-search-central/)
- [OpenAI](https://hiddenradius.com/openai/)
- [Perplexity](https://hiddenradius.com/perplexity/)
- [Microsoft and Bing](https://hiddenradius.com/microsoft-bing/)
- [IETF Robots Standard](https://hiddenradius.com/ietf-robots/)
- [W3C Accessibility](https://hiddenradius.com/w3c-accessibility/)
- [Schema.org](https://hiddenradius.com/schema-org/)
- [Original GEO Research](https://hiddenradius.com/original-geo-research/)
- [Original RAG Research](https://hiddenradius.com/original-rag-research/)
- [REG Origin](https://hiddenradius.com/reg-origin/)

## Application
- [Business Examples](https://hiddenradius.com/business-examples/)
- [Implementation Playbook](https://hiddenradius.com/implementation-playbook/)
- [Audit Methodology](https://hiddenradius.com/audit-methodology/)
- [Measurement and Metrics](https://hiddenradius.com/measurement-metrics/)
- [Services](https://hiddenradius.com/services/)
- [FAQ](https://hiddenradius.com/faq/)
- [Contact](https://hiddenradius.com/contact/)

## Machine-readable resources
- [Site graph](https://hiddenradius.com/site-graph.jsonld)
- [Glossary JSON](https://hiddenradius.com/data/glossary.json)
- [Comparison CSV](https://hiddenradius.com/data/comparison-matrix.csv)
- [Bibliography JSON](https://hiddenradius.com/data/bibliography.json)
- [Knowledge map JSON](https://hiddenradius.com/data/knowledge-map.json)
- [Full LLM summary](https://hiddenradius.com/llms-full.txt)

## Source and company notes
Hidden Radius is a standalone U.S. company. IRefer Club is cited only as the original source organization for Recognition Engine Guidance and Retrieval Engine Guidance. The other institutions and platforms cited do not endorse Hidden Radius unless explicitly stated.

## Limitations
Hidden Radius explains and audits controllable evidence and observable outcomes. Outside platforms control their own crawling, indexing, retrieval, generation, citations, ranking and recommendations.