The lectures are currently (mostly) formatted as plain text, but with some use of unicode characters with the UTF-8 encoding. This means that this character encoding must be activated in browsers when viewing the lectures files, or they must be viewed in an editor that can be configured to display UTF-8 characters properly.
The text files were produced in the emacs editor (Aquamacs on a Mac) and the unicode characters were entered using a set of emacs abbreviations contained in the file unicode-abbrevs which can be loaded with the emacs load<\tt> command.