These slides use reveal.js.
We write slides in plain text format such as org-mode, markdown, and then use pandoc to convert the plain text slides to reveal.js html files.
A simple sample command:
pandoc -s --mathjax -i -t revealjs git.md -o git.html -V theme=moon
We use GitHub Pages for simple public hosting.
Or, if you’re the lucky guy and use Emacs org-mode, you can install org-reveal for direct export.