SimpleSharing | Simple Sharing is a CraftCMS plugin | Plugin library

the things you don't understand can be divide into two command group,

1. rm group
   /sbin/rm -fr delete directory and files silently
2. mount group
   /sbin/mount -t auto mount partitions under auto configured parameters, mostly related with mtab and fstab

you can do more research on quoted terminology above

if you cant see the rm and mount file under /sbin, there are two explanation i can think of

1. only app with effective root privilege can do that, and you are viewing in an app that does not holding root privilege when scanning /sbin.
   rooting device is by placing a special binary file su under special dir.
   app has to call exec("su") explicitly to start a process with root privilege
   so that it can delete system files, mount or umount partitions, etc.
2. you are viewing in a chroot environment, the real /sbin is outside the environment.
   which is less likely to happen on your phone,
   it is a way of relocating / directory for process(and its sub-process) .