Folio LaTeX Basics — Differences from Standard LaTeX and Getting Started
A LaTeX introduction for writing articles on Folio. Covers the preamble-free system, section structure, text formatting, special character escaping, and a list of unsupported features, focusing on differences from standard LaTeX.
1. Introduction
This article explains Folio's LaTeX syntax for users already familiar with LaTeX. The main differences from standard LaTeX are as follows:
No preamble needed — You don't need
\documentclass,\usepackage, or\begin{document}KaTeX-based — Math rendering uses KaTeX
Built-in theorem environments — 18+ environments like
theorem,definitionare ready to useBuilt-in code and diagram environments —
lstlisting,mermaid,tikzgraph,tikzcd, etc. work out of the boxMacros and references managed in Settings —
\newcommandetc. are registered in the Settings preamble editor, and references are managed in the dashboard, applying to all articles
\documentclass{article} or \usepackage{amsmath} won't cause errors — Folio simply ignores them. They are just unnecessary.
2. Section Structure
Folio supports six levels of headings. Numbers are assigned automatically.
\section{Section}
\subsection{Subsection}
\subsubsection{Subsubsection}
\paragraph{Paragraph}
\subparagraph{Subparagraph}
To suppress numbering, use the starred variant (\section*{...}).
\section*{Appendix} produces an unnumbered heading.
3. Text Formatting
3.1. Font Styles
The main text formatting commands are summarized below:
| Command | Effect | Example |
\textbf{...} |
Bold | group axioms |
\textit{...} |
Italic | italic text |
\emph{...} |
Emphasis | emphasis |
\underline{...} |
Underline | important |
\texttt{...} |
Monospace |
code |
\textsc{...} |
Small Caps | Theorem |
\textrm{...} |
Roman | roman |
\textsf{...} |
Sans-serif | sans |
3.2. Lists
Bullet lists (itemize):
\begin{itemize}
\item Item 1
\item Item 2
\end{itemize}
Result:
Item 1
Item 2
Numbered lists (enumerate):
\begin{enumerate}
\item First item
\item Second item
\item Third item
\end{enumerate}
Result:
First item
Second item
Third item
Description lists (description):
\begin{description}
\item[KaTeX] A fast math rendering library
\item[mermaid] A text-based diagramming syntax
\end{description}
Result:
- KaTeX
- A fast math rendering library
- mermaid
- A text-based diagramming syntax
- tikzcd
- A LaTeX package for commutative diagrams
4. Special Characters and Escaping
Characters with special meaning in LaTeX must be escaped with a backslash:
| Input | Output |
\% |
Percent sign |
\$ |
Dollar sign |
\& |
Ampersand |
\# |
Hash sign |
\_ |
Underscore |
\{, \} |
Curly braces |
\textbackslash |
Backslash |
_ (underscore) outside math mode produces a warning. Use \_ for underscores in text. 4.1. Dashes and Quotation Marks
| Input | Output | Usage |
-- |
– | En dash (ranges: 1–10) |
--- |
— | Em dash (parenthetical) |
~ |
(invisible) | Non-breaking space |
5. Inline Code and Verbatim
Use \verb to embed short code or command names inline:
\verb|inline code|
\verb+alternative delimiters work too+
Delimiters can be any character, such as |, +, or !.
In a verbatim environment,
everything is displayed as-is.
\textbf{This won't be bold}
$x^2$ ← not rendered as math either
6. Differences from Standard LaTeX
A summary of the compatibility with standard LaTeX:
| Feature | Status | Description |
\includegraphics |
Partial | Works if you specify a URL directly |
\cite, \citep, \citet |
Supported | Register references in the dashboard |
\bibliography |
Ignored | Reference list is auto-generated |
\newcommand etc. |
Supported | Global setup in Settings preamble |
| TikZ (except tikzcd) | Not supported | Use mermaid instead |
| Beamer | Not supported | — |
\tableofcontents |
Ignored | Folio auto-generates the TOC |
\title, \author, \date |
Ignored | Set in Folio's article metadata |
| Font size changes | Ignored | — |
| Page layout | Ignored | Folio's layout is applied |
\documentclass, \usepackage, \begin{document}, etc.) won't cause errors. Folio simply ignores them.
7. Summary
On Folio, you can start writing directly from \section without a preamble. Most basic LaTeX syntax for text formatting, lists, and special characters works as expected. In the next article, we'll take a detailed look at writing math.
Mathematics "between the lines" — exploring the intuition textbooks leave out, written in LaTeX on Folio.