Because there are only 64 Bytes(4*16) spaces in MBR(master boot record - keeps the information about partions of HDD and booting information from where computer will boot) for creating four partitions in a HDD
By default C: is the active partition of the hard disk drive
A local disk is any hard drive or disk partition on the computer in question. So in order to "create" one, you need to either add a new hard drive, or partition the existing one.
A local disk is any hard drive or disk partition on the computer in question. So in order to "create" one, you need to either add a new hard drive, or partition the existing one.
The OS is stored in the Hard Disk of the computer.
On a Windows 98 system, there is very likely to only be one partition on the disk. The difference between formatting the disk and deleting the partition would thus be a matter of semantics. Either way, all the data on the hard drive would be gone.
In Windows XP there is a way to partition a disk without having to use the Command Line Interface. If you go to Start then right click on My Computer and go to Manage, then Disk Management, a graphical user interface will show you the layout of your hard drive. Then you can right click on the hard drive you want to partition and then select New Partition (or New Primary Drive or something like that). Then just follow the instructions and you can partition the disk however you want.
Disk management
There are many ways, but the easiest is to use a Windows 7 installation disk to delete the partition.
Go to control panel - administrative tools - disk management. There will be all the tools in a handy console to format and partition your hard drive.
Use Disk Utility to format or partition hard drives. You should back up the drive before formatting or partitioning.
partition hard disk
Modern disk drive construction more or less requires drives to have at least one partition. Whether the drive is internal or external is immaterial.