These are Linux 2.4.5 based Slackware bootdisks.

Slackware 2.2.19 is still the default (and recommended) kernel, because
based on our tests it seems more stable, but the 2.4.x kernel series does
have better performance and more features like ReiserFS, an advanced
journaling filesystem, so these bootdisks are provided for those who want
to try out the latest and greatest:

bare.i:  For systems with only IDE drives.
adaptec.s:  For systems with IDE and/or Adaptec SCSI connected drives.
ncr_sym.s:  For systems with IDE and/or NCR/Symbios SCSI connected drives.