One example from the modified remastersys bash script you've already seen:
if [ "$FSTYPE" = "reiserfs" ]; then
mkfs.reiserfs /dev/$TARGETPART
elif [ "$FSTYPE" = "xfs" ]; then
mkfs.xfs /dev/$TARGETPART
else
mke2fs -t $FSTYPE /dev/$TARGETPART
fi
TRANSLATION:
If the chosen filetype is reiser, then
make a reiser filesystem on the target partition
or if the chosen filetype is xfs, then
make an xfs filesystem on the target partition
otherwise
make an ext filesystem of the chosen type (2,3 or 4) on the target partition
-end of if loop-
Here's one more example, using or.
if [ "$FSTYPE" = "ext2" ] || [ "$FSTYPE" = "ext3" ] || [ "$FSTYPE" = "ext4" ]
then
echo "Using tune2fs to prevent the forced checks on boot"
tune2fs -c 0 -i 0 /dev/$TARGETPART
fi
TRANSLATION:
if the filetype is ext2 or ext3 or ext4
then
echo message to the terminal (stdout)
tune2fs with parameters to turn off filechecks based on time lapsed or number of reboots since last check
-end of if loop-