https://mirrors.slackware.com/slackware/slackware-current/source/a/syslinux/

SYSLINUX/PXELINUX/ISOLINUX boot loaders)

SYSLINUX is a boot loader for the Linux operating system which
operates off an MS-DOS/Windows FAT filesystem. This is used by the
Slackware makebootdisk script to create system boot floppies.

Also included are PXELINUX and ISOLINUX, boot loaders for booting from
a network server or CD-ROM.

SYSLINUX, PXELINUX, and ISOLINUX were written by H. Peter Anvin.