LaTeX Cheatsheet

This cheatsheet covers common LaTeX commands and environments for quick reference.

Document Structure

Document Class: Defines the type of document.

\documentclass[options]{class}
% Common classes: article, report, book, letter, beamer
% Common options: 10pt, 11pt, 12pt, a4paper, letterpaper, twocolumn, landscape

Packages: Add functionality.

\usepackage[options]{package}
% Essential packages:
\usepackage[utf8]{inputenc} % Input encoding (often default now)
\usepackage[T1]{fontenc}    % Font encoding (better font handling)
\usepackage{amsmath}      % Advanced math environments and symbols
\usepackage{graphicx}     % Include images (\includegraphics)
\usepackage{hyperref}     % Creates hyperlinks within the document (PDF)
\usepackage{geometry}     % Customize page margins (e.g., \usepackage[margin=1in]{geometry})

Preamble: Area between \documentclass and \begin{document} for loading packages and setting definitions.

Document Body: Main content area.

\begin{document}
% Your content goes here
\end{document}

Title, Author, Date:

\title{My Document Title}
\author{Your Name}
\date{\today} % Or specify a date like \date{October 26, 2023}

\begin{document}
\maketitle % Displays the title/author/date block
...
\end{document}

Basic Text Formatting

Bold: \textbf{text}
Italics: \textit{text}
Underline: \underline{text} (Often typographically discouraged)
Emphasis: \emph{text} (Context-aware italics/roman)
Typewriter: \texttt{text}
Small Caps: \textsc{text}
Font Sizes (Switches):
- {\tiny ...}
- {\scriptsize ...}
- {\footnotesize ...}
- {\small ...}
- {\normalsize ...} (Default)
- {\large ...}
- {\Large ...}
- {\LARGE ...}
- {\huge ...}
- {\Huge ...}
Paragraphs: Separate paragraphs with a blank line in the source code.
Line Break: \\ or \newline (Use sparingly; usually better to let LaTeX handle line breaks).
New Page: \newpage or \clearpage (flushes floats)

Sections and Structure

Chapters (Book/Report): \chapter{Chapter Title}
Sections: \section{Section Title}
Subsections: \subsection{Subsection Title}
Subsubsections: \subsubsection{Subsubsection Title}
Paragraphs: \paragraph{Paragraph Title} (Acts like a heading)
Subparagraphs: \subparagraph{Subparagraph Title}
Unnumbered Sections: Add * (e.g., \section*{Unnumbered Section})
Table of Contents: \tableofcontents (Requires 2-3 LaTeX compilations)

Abstract:

\begin{abstract}
Summary of your document.
\end{abstract}

Lists

Unordered (Bullet):

\begin{itemize}
  \item First item
  \item Second item
    \begin{itemize}
      \item Nested item
    \end{itemize}
\end{itemize}

Ordered (Numbered):

\begin{enumerate}
  \item First item
  \item Second item
\end{enumerate}

Description (Labeled):

\begin{description}
  \item[Label 1] Description text.
  \item[Word] Definition of the word.
\end{description}

Math Mode

Inline Math: $ E = mc^2 $ or $ E = mc^2 $
Display Math (Unnumbered): \[ \sum_{i=0}^{n} i = \frac{n(n+1)}{2} \]

Display Math (Numbered): (Requires amsmath)

\begin{equation} \label{eq:euler}
e^{i\pi} + 1 = 0
\end{equation}

Unnumbered Equation: (Requires amsmath)

\begin{equation*}
\int_{-\infty}^{\infty} e^{-x^2} dx = \sqrt{\pi}
\end{equation*}

Align Environment: (Requires amsmath) For aligning multiple equations.

\begin{align}
a &= b + c \\ \label{eq:align}
d &= e + f + g
\end{align}

Common Math Symbols/Commands

| Command | Symbol/Output | Notes | | :--------------------- | :------------------------------------ | :------------------------------------------------------ | ---------- | --- | | ^ | Superscript (x^2) | x^{10} for multiple characters | | _ | Subscript (x_1) | x_{ij} for multiple characters | | \frac{num}{den} | Fraction | | | \sqrt{expr} | Square root | \sqrt[n]{expr} for n-th root | | \sum, \int, \lim | Summation, Integral, Limit | Use _ and ^ for limits/bounds | | \alpha, \beta, ... | Greek letters | \Gamma, \Delta, ... for uppercase | | \sin, \cos, \log | Standard functions (roman) | | | \times, \cdot | Multiplication symbols | \times, \cdot | | \leq, \geq, \neq | Less/Greater than or equal, Not equal | \le, \ge, \ne are synonyms | | \infty | Infinity symbol | | | \dots, \cdots | Ellipsis (low, centered) | \vdots, \ddots for vertical/diag | | \{ \} | Curly braces | Need backslash: \{, \} | | \left( ... \right) | Auto-sizing parentheses | Also \left[, \right], \left\{, \right\}, \left | , \right | | | \mathbf{X} | Bold math symbols | | | \mathcal{L} | Calligraphic letters | | | \mathbb{R} | Blackboard bold (needs amsfonts) | Common for sets (R, C, N, Z) |

Figures & Tables

Including Figures: (Requires graphicx package)

\begin{figure}[htbp] % Placement options: h=here, t=top, b=bottom, p=page of floats
  \centering % Center the figure
  \includegraphics[width=0.8\textwidth]{image_filename} % Include image (no extension needed usually)
  \caption{Caption text for the figure.}
  \label{fig:myfigure} % Label for cross-referencing
\end{figure}

\includegraphics options: width=, height=, scale=, angle=

Basic Table:

\begin{table}[htbp]
  \centering
  \caption{Caption text for the table.}
  \label{tab:mytable}
  \begin{tabular}{|l|c|r|} % Column spec: l=left, c=center, r=right, |=vertical line
    \hline % Horizontal line
    Header 1 & Header 2 & Header 3 \\ % Column headers, & separates columns, \\ ends row
    \hline
    Row 1, Col 1 & R1C2 & R1C3 \\
    Row 2, Col 1 & R2C2 & R2C3 \\
    \hline
  \end{tabular}
\end{table}

\hline: Full horizontal line
\cline{i-j}: Partial horizontal line spanning columns i to j

Cross-Referencing

Labeling: Use \label{marker} inside figure, table, equation environments, or after \section, \item, etc.
- Common prefixes: fig:, tab:, eq:, sec:, itm:
Referencing:
- \ref{marker}: Prints the number (e.g., figure number, equation number, section number).
- \pageref{marker}: Prints the page number where the label occurs.
- Eq.~\eqref{eq:marker}: Prints equation number in parentheses (requires amsmath).
- Requires 2-3 LaTeX compilations to resolve references correctly.

Bibliography (using BibTeX)

Create a .bib file (e.g., references.bib) with entries like:

@article{einstein1905,
  author  = {Albert Einstein},
  title   = {Zur Elektrodynamik bewegter K{\"o}rper},
  journal = {Annalen der Physik},
  volume  = {322},
  number  = {10},
  pages   = {891--921},
  year    = {1905},
}

@book{knuth1984texbook,
  author    = {Donald E. Knuth},
  title     = {The {\TeX}book},
  publisher = {Addison-Wesley},
  year      = {1984},
}

In your LaTeX document:
- Cite sources: \cite{key} (e.g., \cite{einstein1905}). Multiple: \cite{key1, key2}.
- Specify bibliography style (in preamble or before \bibliography): \bibliographystyle{plain} (Common styles: plain, unsrt, alpha, abbrv)
- Generate bibliography: \bibliography{references} (Use the .bib filename without the extension)
Compilation Process: pdflatex yourfile, bibtex yourfile, pdflatex yourfile, pdflatex yourfile.

Special Characters & Symbols

Reserved Characters: Need backslash \ to print: \# \$ \% \& \_ \{ \} \~ \^
Backslash: \textbackslash
Ellipsis: \dots (low) or \ldots
Dashes:
- - Hyphen (e.g., well-known)
- -- En-dash (e.g., pages 10--20)
- --- Em-dash (e.g., Yes---absolutely!)
Quotes:
- `` for opening double quotes (“)
- '' for closing double quotes (”)
- ` for opening single quote (‘)
- ' for closing single quote (’)
Tilde: ~ (Non-breaking space, useful e.g., Fig.~1)
Degree Symbol: \textdegree (requires textcomp) or $^\circ$ (in math mode)
Euro Symbol: \texteuro (requires textcomp or specific font setup)

Comments

Use the percent sign %. Everything from % to the end of the line is ignored.

This is normal text. % This is a comment and will not be shown.
% This entire line is a comment.

Compilation

Common command-line compilers: pdflatex, xelatex, lualatex. pdflatex is the most traditional.
Compile multiple times (usually 2-3) to resolve references, table of contents, and bibliography correctly.