Make Beamer slides 16:9

Beamer is an ergonomic tool to generate slides from raw text files with LaTeX. A minimal example is

\documentclass{beamer}

\begin{document}

\begin{frame}
    Hello!
\end{frame}

\end{document}

By default, Beamer slides have an aspect ratio of 4:3, while most modern projectors and screens have the 16:9 aspect ratio. To fill the entire screen, a simple modification is to add the aspectratio=169 option to the documentclass:

\documentclass[aspectratio=169]{beamer}

Microsoft Powerpoint and Google Slides both set the aspect ratio to 16:9 by default. Beamer users should do the same.