% "30m" but took me 2h.  Very informative.  I've copy pasted the examples here
% to play with them.  Reading this tutorial before starting big LaTeX projects
% (like my thesis) would've been very beneficial and safe me some time and
% headaches.  I'm happy I've read it and completed it now,  some concepts are
% now much clearer.
%
% Ref.: https://www.overleaf.com/learn/latex/Learn_LaTeX_in_30_minutes

% preamble ("setup" section)
% ============================================================================
\documentclass[12pt, a4paper]{article}
% document class: article (other options include book and report)
% aditional options: 12pt font (default is 10pt), a4paper size

% Loading packages `\usepackage[options]{package}`
\usepackage{graphicx}
\graphicspath{{img/}}
\usepackage{amsmath}    % For the "equation*" environment
\usepackage{parskip}    % Used to typeset paragraphs with larger spacing
% \usepackage[
%     total={6.5in,8.75in},
%     top=1.2in, left=1.0in, includefoot
% ]{geometry}

\title{My first LaTeX document}
\author{Hubert Farnsworth\thanks{Funded by the Overleaf team.}}
\date{September 2023}
% \date{\today}


% actual content
% ============================================================================
\begin{document}
\maketitle
\tableofcontents
\begin{abstract}
    This is a simple paragraph at the beginning of the document. A brief
    introduction about the main subject.
\end{abstract}

% \part{Learn}

% \chapter{Learn \LaTeX}

\section{Basic typesetting}

First document. This is a simple example, with no extra parameters or packages
included.

We have now added a title, author and date to our first \LaTeX{} document!

Some of the \textbf{greatest}
discoveries in \underline{science} 
were made by \textbf{\textit{accident}}. (\textit{italics}.)

% emphasize (toggles italics depending on context)
% (some packages, such as Beamer, change the behaviour of the \emph command.)
Some of the greatest \emph{discoveries} in science were made by accident.

\textit{Some of the greatest \emph{discoveries} in science were made by accident.}


% "starred version" of the appropriate command 
\section*{Unnumbered section}
% unnumbered sections aren't added to the TOC by default
\addcontentsline{toc}{section}{Unnumbered Section}

Lorem  ipsum  dolor  sit  amet,  consectetuer  adipiscing  
elit. Etiam  lobortisfacilisis sem.  Nullam nec mi et 
neque pharetra sollicitudin.  Praesent imperdietmi nec ante. 
Donec ullamcorper, felis non sodales...


\section{Figures}

% images

% The \includegraphcs command is provided (implemented) by the graphicx package
Lorem Ipsum Lorem Ipsum Lorem Ipsum 
How is text rendered just before an image?
\includegraphics[width=0.25\textwidth]{rocas}
How is text rendered right after an image?

% figures: captions, labels, references

\begin{figure}[h]
    % Code here is encapsulated by the "figure" environment
    \centering
    \includegraphics[width=0.15\textwidth]{rocas}
    \includegraphics[width=0.30\textwidth]{rocas}
    \includegraphics[width=0.60\textwidth]{rocas}
    \caption{From the top left, clockwise: Unas roquitas relajandose, unas rocas
    relajandose, unas rocotas relajandose.}     
    % Caption can be placed above or below the list of figures
    \label{fig:rocas}
\end{figure}
 
As you can see in figure \ref{fig:rocas}, the rocks are happyto see their owner.
(This example is on page \pageref{fig:rocas}.)


\section{Lists}

% lists

\begin{itemize}
    \item The individual entries are indicated with a black dot, a so-called bullet.
    \item The text in the entries may be of any length.
\end{itemize}

\begin{enumerate}
    \item This is the first entry in our list.
    \begin{enumerate}
        \item This is the 1.1 entry in our list.
        \begin{enumerate}
            \item This is the 1.1.1 entry in our list. Things begin to look messy
            \begin{enumerate}
                \item This is the 1.1.1.1 entry in our list. Things begin to look messy
                in the source code.
                % Maximum default depth (4) reached, further is invalid
                % \begin{enumerate}
                %     \item This is the 1.1.1.1 entry in our list. Things begin to look messy
                %     in the source code.
                %     \item The list numbers increase with each entry we add.
                % \end{enumerate}
                \item The list numbers increase with each entry we add.
            \end{enumerate}
            in the source code.
            \item The list numbers increase with each entry we add.
        \end{enumerate}
        \item The list numbers increase with each entry we add.
    \end{enumerate}
    \item The list numbers increase with each entry we add.
\end{enumerate}


\section{Math}

% math

% inline math uses the "math" environemnt
\begin{math} E=mc^2 \end{math} is typeset in a paragraph using inline math
mode---as is $E=mc^2$, and so too is \(E=mc^2\).

% display math  uses the "displaymath" or the "equation" environment
% (usage of $$ is no longer recommended).
The mass-energy equivalence is described by the famous equation
\[ E=mc^2 \] discovered in 1905 by Albert Einstein. 
In natural units ($c = 1$), the formula expresses the identity
\begin{equation} E=m \end{equation}

% more examples

Subscripts in math mode are written as $a_b$ and superscripts are written as
$a^b$. These can be combined and nested to write expressions such as

\[ T^{i_1 i_2 \dots i_p}_{j_1 j_2 \dots j_q} =
T(x^{i_1},\dots,x^{i_p},e_{j_1},\dots,e_{j_q}) \]

We write integrals using $\int$ and fractions using $\frac{a}{b}$. Limits are
placed on integrals using superscripts and subscripts:

\[ \int_0^1 \frac{dx}{e^x} =  \frac{e-1}{e} \]

Lower case Greek letters are written as $\omega$ $\delta$ etc. while upper case
Greek letters are written as $\Omega$ $\Delta$.

Mathematical operators are prefixed with a backslash as $\sin(\beta)$,
$\cos(\alpha)$, $\log(x)$ etc.

% amsmath package:
\begin{equation*}
    \sqrt{x^2+1}
\end{equation*}

% manual newline

I will start the third paragraph and then add \verb`\\`\\ a manual line break which
causes this text to start on a new line but remains part of the same paragraph.
Alternatively, I can use the \verb|\newline|\newline command to start a new
line, which is also part of the same paragraph.

% Longer documents, irrespective of authoring software, are usually partitioned
% into parts, chapters, sections, subsections and so forth.

\section{Document Structure}

Collectively, LaTeX document classes provide the following sectioning commands,
with specific classes each supporting a relevant subset:

\begin{verbatim}
    \part{part}
    \chapter{chapter}
    \section{section}
    \subsection{subsection}
    \subsubsection{subsubsection}
    \paragraph{paragraph}
    \subparagraph{subparagraph}

In particular, the \part and \chapter commands are only 
available in the report and book document classes. 
\end{verbatim}

\section{Tables}

TIP: Creating tables in LaTeX can be time-consuming so you may want to use the
https://tablesgenerator.com online tool to export LaTeX code for tabulars.

\begin{center} 
\begin{tabular}{c c c}
    % alignment: Center, Right, Left
    % &: alignment symbol
    % \\: newline
    cell1 & cell2 & cell3 \\ 
    cell4 & cell5 & cell6 \\  
    cell7 & cell8 & cell9    
\end{tabular} 

% adding borders (rules)
\begin{tabular}{||c l c r||} 
    \hline
    Col1 & Col2 & Col2 & Col3 \\ [0.5ex]    % control extra spacing
    \hline\hline
    1 & hola & 87837 & 787 \\ 
    \hline
    2 & mundo & 78 & 5415 \\
    \hline
    % 3 & 世界、 & 778 & 7507 \\
    % \hline
    % 4 & こんにちは & 18744 & 7560 \\
    % \hline
    5 & hello world! & 788 & 6344 \\ [1ex] 
    \hline
\end{tabular}
\end{center}

% To add captions, labels, and references use the Table environment

Table \ref{table:data} shows how to add a table caption and reference a table.
\begin{table}[h!]
\centering
\begin{tabular}{||c c c c||} 
 \hline
 Col1 & Col2 & Col2 & Col3 \\ [0.5ex] 
 \hline\hline
 1 & 6 & 87837 & 787 \\ 
 2 & 7 & 78 & 5415 \\
 3 & 545 & 778 & 7507 \\
 4 & 545 & 18744 & 7560 \\
 5 & 88 & 788 & 6344 \\ [1ex] 
 \hline
\end{tabular}
\caption{Table to test captions and labels.}
\label{table:data}
\end{table}

\section{Finding and using LaTeX packages}

Documentation (in pdf format) in
\begin{verbatim}
~/code/tex-live-native/build/texmf-dist/doc/latex
\end{verbatim}

\LaTeX packages usually have ".sty" extension.

Packages are distributed through the Comprehensive TeX Archive Network 
(https://www.ctan.org/), usually referred to as CTAN.

Once per year a (large) subset of packages hosted on CTAN, plus LaTeX-related
fonts and other software, is collated and distributed as a system called TeX
Live (https://tug.org/texlive/), which can be used to install your own (local)
LaTeX setup.

Overleaf (https://www.overleaf.com) makes available thousands of templates in
their gallery (https://www.overleaf.com/gallery).

Some nice packages like https://ctan.org/pkg/igo?lang=en are hosted on CTAN
but not distributed by TeX Live due to a variety of reasons: perhaps a package
is obsolete, has licensing problems, is extremely new (recently uploaded) or has
platform dependencies, such as working on Windows but not Linux. 

\end{document}