PDF File Number URLs

Just curious why the URL for a pdf file is so long: http://alplm-cdi.com/chroniclingillinois/files/original/6f1894852438c8fa539505e35fee7b93.pdf

when the original file number is 300001.pdf.?

Besides the site URL information,is this just the way Omeka displays URL's for pdfs or is there another reason?

Thank You,

RBM

All files get a name based on some random data to avoid name collisions in case two people add different files with the same name.

Thanks!