LaTeX makes it fairly easy to include most common image files. Typically something like
\usepackage{graphicx}is all you need. LaTeX apparently doesn't play nicely with .eps files by default, however, presenting "Unknown graphics extension: .eps". This is unfortunate because .eps files are vector images, meaning they retain their quality when being scaled up. This is helpful because the images Matlab generates, for example, are typically small.
\includegraphics[width=0.75\textwidth]{image.png}
\usepackage{epstopdf}fixes the problem like a charm.