Lesson 5 of 8

Figures and Images: Including, Sizing, and Captioning

~8 min read

By the end of this lesson you can insert an image, scale it, give it a caption and label, position it, and refer to it by number. Load graphicx, then use \includegraphics inside a figure environment.

Loading graphicx and inserting an image

Add \usepackage{graphicx} to the preamble, then place the image with \includegraphics. Upload the image file into your project so LaTeX can find it.

\usepackage{graphicx}   % in the preamble
% ...
\includegraphics[width=0.8\linewidth]{diagram.png}

Sizing options

Option	Effect
width=0.8\linewidth	Scale to 80% of the text width
width=5cm	Fixed width of 5 cm
height=4cm	Fixed height
scale=0.5	Scale to 50% of natural size
angle=90	Rotate 90 degrees

The figure environment: captions and labels

Wrap the image in a figure environment to add a numbered caption and a label you can reference. \centering centers it.

A complete, referenceable figure

\begin{figure}[ht]
  \centering
  \includegraphics[width=0.8\linewidth]{diagram.png}
  \caption{System architecture overview.}
  \label{fig:arch}
\end{figure}

As shown in Figure~\ref{fig:arch}, the system has three layers.

The ~ in Figure~\ref{...} is a non-breaking space — it keeps “Figure” and the number together on the same line.

Placement: where figures land

The optional [ht] is a placement hint — LaTeX floats figures to a convenient spot. Common specifiers:

h — “here”, approximately where written
t — top of a page
b — bottom of a page
p — a dedicated page of floats
! — try harder to honor your request (e.g. [!ht])

For an image that must appear exactly where written, load \usepackage{float} and use [H].

Supported formats

pdflatex accepts .png, .jpg, and .pdf. Vector graphics (PDF) stay crisp at any size — prefer them for diagrams and plots.

Frequently asked questions

My image does not appear — why?

Check that the file is uploaded to the project, the filename matches exactly (case-sensitive), and graphicx is loaded. The LetX file browser shows what is available to include.

How do I put two images side by side?

Use two \includegraphics inside one figure, or the subcaption package with subfigure environments for individually captioned panels.

How do I force a figure to stay in place?

Load \usepackage{float} and use the [H] specifier: \begin{figure}[H]. This disables floating for that figure.