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-# What is a TeachBook?
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+# What is a TeachBook?
+
+
+Anatomy of a Book
+
+
+Three parts to a book:
+1. A configuration file, `_config.yml`
+2. A table of contents file, `_toc.yml`
+3. Content for your book! Text-based files.
+
+```{admonition} Text-based files? yml? What is that?!
+:class: tip
+
+Text-based files are digital files on your computer that you can open in a text editor and read directly. There are many file extensions used for text-based files, a few common ones related to Jupyter Book are: Markdown (`*.md`), Jupyter Notebooks (`*.ipynb`), and YAML (`*.yml`).
+
+YAML (or YML) is a text-based file format that is primarily used to store data. It is useful because it is easy for humans to read and write, and easy for machines to _parse_ and generate., which is why YAML is often used for configuration files. Here is an example of a YAML file...can you tell what information is being stored?
+
+
+```
+
+## How a book is made
+
+1. Content is written in text-based files such as Markdown (`*.md`), Jupyter Notebooks (`*.ipynb`), etc.
+2. Software is used to "parse" these files and create the final book (e.g., Jupyter Book)
+
+
+A hint of the key tools
+- Python
+- Git and GitHub
+- A web browser
+
+```{admonition} Comparing and Contrasting to LaTeX
+
+Have you ever used LaTeX? It turns out there are a lot of similarities with this document system. Here is a quick list:
+1. Writing "source code" in text-based files (i.e., `*.tex` versus `*.md`, `*.ipynb`, etc) that is generally easy to read without the markup and uses special functions to format rich document objects (e.g., tables, figures, etc).
+2. The "book" is created by using a piece of software that parses the source code and creates the final document (a `*.pdf` versus a `*.html` for Jupyter Book).
+3. Creating the document structure using a list of files that contain source code that automatically generates the Table of Contents and Index..
+4. Sometimes you can spend more time than you like troubleshooting "bugs" that turn out to be simple syntax errors.
+``` 
+
+
+the rest is just 
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