How to prevent figures and tables from floating

Many times I received messages like

  LaTeX Warning: `!h' float specifier changed to `!ht'.

resulting my figures / tables appearing on the top of the page, however I wanted to place the figure _exactly_ where at that position.

TThe solution I found here is to use the package float

\usepackage{float}
...
\begin{figure}[H]
...
\end{figure}