Hard disks are used for storing data. Hard disks can have different capacities like 40 gigabytes hard disk, 80 gigabytes hard disk, 160 gigabytes hard disk and other hard disk which is more than 160 gigabytes hard disk and less than 40 gigabytes hard disk. Hard disk is most important part of computer because without it we cannot run the computer. Hard disk can be internal and external.

 Hard disk helps to copy data from removable drive and other removable storages. Hard disk also helps to copy its data to CD, DVD and other removable drive. We can do copy and delete data in hard disks.