---
title: "Concepts"
description: "The mental model of Notarium: how data, search, versions, and access work."
---

# Concepts

How Notarium works under the hood — the ideas the product is built on. Read this to understand the "why," not the "where to click" (that lives in "Working in Notarium").

## In this section

- **File-first** — files as the source of truth.
- **Humans and agents** — one shared knowledge base on a single core.
- **Spaces and projects** — the units of isolation and organization.
- **Knowledge graph** — connections between notes.
- **Hybrid search** — lexical + semantic + graph.
- **Version history** — the revision log.
- **Access model** — membership, roles, privacy.
- **Note types** — kinds of content.