Therefore a 1.7 GIG hard drive formatted with a single 16-bit FAT partition will have a cluster size of 32,768 bytes. The reason that cluster size is so important is that a file may not take up an entire cluster. A file that is 433 bytes in actual size on a partition with a cluster size of 8096 takes up 8096 bytes of hard disk space, not 433. This is wasted space. A file takes up a minimum of 1 cluster.
Lets take a look of two computers.
These are actual computers. The size of the partition of the drive is in the column marked size. The number of files on that partition is i the column marked files . A file that takes up 1 byte wastes almost all of the cluster. A file that takes up a entire cluster wastes no space.