> ## Documentation Index
> Fetch the complete documentation index at: https://docs.userintuition.ai/llms.txt
> Use this file to discover all available pages before exploring further.
> Understand the core concepts behind User Intuition: studies, interviews, the moderator, and the Intelligence Hub — and how they fit together.
# Key Concepts
A few concepts shape how everything on the platform works. Worth five minutes before you build your first study.
***
## Studies
A **study** is a research project focused on a specific question. Each one has:
* **A research plan** — the objective, learning goals, key questions, and conversation flow
* **An interview setup** — moderator voice, format, language, recruiting method, and screeners
* **Participants** — who you've invited and where they've got to
* **Results** — completed interviews, transcripts, and reports
### Study types
There are three. All follow the same setup process; what differs is whether participants react to something, and what.
| Type | Best for |
| ---------------------- | ----------------------------------------------------- |
| **In-depth Interview** | Experiences, motivations, and decisions — no stimulus |
| **Concept Test** | Reactions to an image or video |
| **Prototype Test** | Watching people work through a prototype or live site |
What each one does and when to reach for it.
***
## Interviews
An **interview** — also called a call — is one conversation between the moderator and one participant. Interviews are:
* **Conversational** — natural dialogue, not a rigid survey
* **Adaptive** — the moderator follows up based on what it hears
* **Deep** — it probes past the first answer to get at the reasoning underneath
* **Recorded** — transcript captured automatically, with audio or video where the format includes it
### Interview formats
| Format | What participants do | Credits |
| --------- | ------------------------------------------------ | ------- |
| **Chat** | Type their responses | 0.5 |
| **Voice** | Speak and hear the moderator | 1 |
| **Video** | Speak on camera, optionally sharing their screen | 2 |
You set the format when you build the study. Participants can't change it.
How chat, voice, and video differ — permissions, screen sharing, and cost.
### Interview quality
Every completed interview is rated **Excellent**, **Good**, **Fair**, or **Poor**, based on how long the conversation ran, how substantive the answers were, and how much of your research plan it actually covered.
***
## Charles, your AI researcher
**Charles** helps you design studies. During setup he asks clarifying questions about your goals, drafts a research plan, and revises it as you give feedback. You work with Charles in chat.
***
## The moderator
The **moderator** is the AI that runs the actual conversations with participants. It follows your research plan while adapting to each conversation, probes deeper when something interesting surfaces, and keeps a warm, professional tone throughout. It achieves 98% participant satisfaction.
Charles and the moderator are different things: **Charles helps you design the study; the moderator runs it.**
***
## Participants
**Participants** are the people who complete your interviews. There are two ways to reach them:
| Approach | Methods |
| ------------------------------- | -------------------------------------------------------- |
| **Bring your own participants** | Share a study link · Send email invites · Embed a widget |
| **Research panel** | Recruit from our panel · Recruit a niche audience |
You choose which when you set up the study, and it determines your invite options on the dashboard.
How to choose, and what each method costs.
***
## Reports
**Reports** synthesize findings across multiple interviews into an executive summary, top insights, analysis by theme, and supporting quotes. They need at least 2 completed interviews and can be regenerated as more come in.
***
## Intelligence Hub
The **Intelligence Hub** is a workspace for analyzing knowledge across studies rather than within one. Sync completed studies, upload external documents, and ask questions in plain language across everything at once. It also generates reports and presentations.
Where a per-study report answers "what did this study find?", the Intelligence Hub answers "what do we know?" — and gets richer with every study you add.
Sync sources, ask questions, and generate outputs.
***
## Key metrics
You'll see these on every study dashboard:
| Metric | Meaning |
| ------------------ | --------------------------------------- |
| **Responses** | Completed interviews |
| **Avg Length** | Average interview duration |
| **Quality** | Responses meeting quality thresholds |
| **Study Progress** | Responses collected against your target |
***
## Credits
Interviews are paid for in **credits**. How many an interview costs depends on its format — chat 0.5, voice 1, video 2 — and what a credit costs depends on your plan. Test conversations are free.
Plans, credit pricing, and panel costs.
***
## Next Steps
* [Quickstart](/getting-started/quickstart) — launch your first study
* [Creating a Study](/creating-a-study/overview) — the full setup guide