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+\documentclass[a4paper]{article}
+\usepackage[a4paper]{geometry}
+\usepackage{miscdoc}
+\usepackage[scaled=0.85]{luximono}
+\begin{document}
+\title{The \Package{captdef} package}
+\author{Robin Fairbairns\thanks{Email: \emph{rf10@cam.ac.uk}}}
+\maketitle
+
+\section{Why this package?}
+
+\LaTeX{} provides a command (\cs{caption}) for adding a caption to a
+float environment (that is to say, a \texttt{figure} or a
+\texttt{table}, ``out of the box'').
+
+The command is a good one, and many users want to use it. Often,
+they end up using a float environment, in a case where it's not
+strictly necessary, and get entangled in the positioning problems
+that floats pose for the innocent user. Using this package, the
+user can have standard-looking captions without the need of a float
+environment.
+
+This package defines a means of defining caption commands, which
+creates things that look as if they were created by \cs{caption}, and
+which work outside of a float.
+
+The \textsf{float} package provides an alternative to
+\cs{captdef}-defined commands, in the float \texttt{[H]} option
+(``place the environment \emph{here} without doing any of this
+floating stuff''). So why use \Package{captdef}?\,---\,its great
+advantage is simplicity; you load it, and it defines just \emph{three}
+macros, while \textsf{float} defines lots and lots. (Of course, if
+you need others of \textsf{float}'s capabilities, \textsf{captdef}
+loses its advantage\dots).
+
+\section{How the package works}
+
+The package defines a command
+\begin{quote}
+ \cmdinvoke*{DeclareCaption}{command}{counter}
+\end{quote}
+which creates a `caption'-like command, which uses \texttt{counter}
+for its numbering.
+
+The package then goes on to declare the commonly-needed caption
+commands \cs{figcaption} and \cs{tabcaption}:
+\begin{quote}
+ \cmdinvoke{captdef}{\cs{figcaption}}{figure}\\
+ \cmdinvoke{captdef}{\cs{tabcaption}}{table}
+\end{quote}
+
+\section{The potential problem}
+
+Commands defined by \cs{captdef} place a caption in text, and also step the
+\environment{figure} (or \environment{table} or whatever) counter. The float
+environments do the same.
+
+Now, consider the sequence:
+\begin{quote}
+\begin{verbatim}
+<earlier text>
+\begin{figure}
+ <figure stuff>
+ \caption{...}
+\end{figure}
+...
+<intervening text>
+...
+<inline figure stuff>
+\figcaption{...}
+\end{verbatim}
+\end{quote}
+and suppose the \environment{figure} environment doesn't fit anywhere
+between where it's specified and the inline figure (so that it will
+float to somewhere later).
+
+We will then see a document with
+\begin{quote}
+\meta{earlier text}\\
+\dots\\
+\meta{intervening text}\\
+\dots\\
+\meta{inline figure stuff}\\
+Figure \meta{n+1}: \dots\\
+\dots\\
+\meta{yet more text}\\
+\dots\\
+\meta{figure stuff}\\
+Figure \meta{n}: \dots
+\end{quote}
+That is, the figure numbers have got out of order, because the
+floating figure was specified before the inline figure.
+
+\LaTeX{} won't do this when everything is specified as a float: it
+keeps floats of the same type in order (which is why floats stack up
+if a single one won't fit).
+
+The moral of that little tale is to say: don't use
+\cs{captdef}-defined commands with floats of the same type in the same
+document. (Or be extra-specially careful about what's happening if
+you must.)
+\end{document}