When data are stored in hard disk, they make cluster as a unit.
In Microsofts operating system (likeDOS, WINDOWS, etc.
), the smallest unit of file management and storage, is called cluster.
A file is usually stored in one or more clusters.
But it should occupy a cluster at least.
That is to say two files cannot be stored in the same cluster.
The original meaning of cluster is a group of or a group.
It means a set ofsectors(a track can be divided into several arc with the same size.
Often, we canchange the size of a cluster.
It is regulated by the command (advanced) format in the operating system.
So the management is more flexible.
In general, file is like a family, and the data is man (or family members).
The so-called cluster is some unit suites.
Sector composes these unit suites.
A family can live in one or more units, but a unit suite can only hold one family.
Thefile systemis a connection between operating system and driver.
Sector is the smallest physical disk storage unit.
By this way, it can form a cluster and then manage the cluster.
Each cluster can include 2, 4, 8, 16, 32, or 64 sectors.
Thus space occupied by the file can only be integer times of the clusters.
Even if the files actual size is smaller than a cluster, it will take up a cluster.
So, the file usually occupies slightly larger space than its actual size.
