---
title: 'What It Is'
url: 'https://levesaudavel.com.br/open-reader-guide/section-1/what-it-is'
markdown: 'https://levesaudavel.com.br/open-reader-guide/section-1/what-it-is.md'
date: '2026-09-14'
description: 'Helios Open Reader provides a ready-built open textbook or reader site using portable Markdown files you fully control. Highlights include a configurable sections structure, a full set of callout blocks, Keep My Place navigation, and optional Git Sync for open collaborative authoring. Reader Struct…'
---

# What It Is

Helios Open Reader provides a ready-built open textbook or reader site using portable Markdown files you fully control. Highlights include a configurable sections structure, a full set of callout blocks, Keep My Place navigation, and optional Git Sync for open collaborative authoring.

## Reader Structure

- **Sections structure** – top-level folders named `section-N` are auto-detected as sections and render as section cards on the reader home
- **Section N header** – section pages automatically display their section number in the page header; inherits correctly for all sub-pages within a section. The label is configurable (e.g. Chapter, Project, Unit, Module) via **Admin → Pages → Reader Home → Section Label**
- **Section sub-pages** – sections can contain any number of sub-pages, all shown in the sidebar and navigable with Prev/Next controls
- Reader home page with cover image, title, subtitle, authors, edition, and CC license badge

## Callout Blocks

- **Learning Objectives** –

`[objectives]...[/objectives]`

(green); also available as frontmatter (`learning_objectives:`) for automatic rendering at the top of a section page

- **Key Takeaways** –

`[key-takeaways]...[/key-takeaways]`

(blue)

- **Example** –

`[example]...[/example]`

(purple)

- **Exercise** –

`[exercise]...[/exercise]`

(amber)

- **Definition** –

`[definition]...[/definition]`

(blue)

- **Reflection** –

`[reflection]...[/reflection]`

(green)

- **Case Study** –

`[case-study]...[/case-study]`

(red)

- **Announcement** –

`[announcement]...[/announcement]`

(purple by default; configurable type)

- All callouts accept an optional `title="..."` parameter and support Markdown content
- Five built-in GitHub-style callouts: `> [!NOTE]`, `> [!TIP]`, `> [!IMPORTANT]`, `> [!WARNING]`, `> [!CAUTION]`

## Navigation & Reading Experience

- **Keep My Place** – records the last section page visited in localStorage; a dismissable "Continue reading" strip appears on the publication home page on return, linking directly to the last section read
- **Reading progress indicator** – shows current page position (e.g. Page 4 of 22) with an accessible progress bar above the Prev/Next navigation on section pages
- **Prev/Next navigation** – configurable position: top, bottom, or both
- **TOC scroll spy** – active heading highlighted in the Table of Contents as the reader scrolls
- **Start Reading button** – on the reader home; links directly to the first section
- Search across the full reader via the simplesearch plugin

 Key Takeaways

- Content lives in portable Markdown files you own and control
- Sections structure is auto-detected from folder naming – no configuration needed
- Callout blocks, Keep My Place, and reading progress are all built in
- The reader works standalone or embedded in any LMS

---

## Navigation

- Parent: [Introduction](https://levesaudavel.com.br/open-reader-guide/section-1.md)
- Next: [When to Use It](https://levesaudavel.com.br/open-reader-guide/section-1/when-to-use.md)