This directory contain music for an "event".
If there is a large .pdf file with the date in its name,
it is the entire set.
It's usually in alphabetical order,
but might be in performance order.
If there's a file with "program" in its name,
it contains information (usually from email messages)
about the event and its program.
The .abc files are the music in ABG music notation,
usually one page per file,
for those who prefer to do their own formatting.
If there's a .pdf file with the same name as a .abc file,
they're for the same page of music.