3 partition
IDE (Integrated Drive Electronics) can support a maximum of four primary partitions on a single hard drive. Alternatively, one of these primary partitions can be configured as an extended partition, which can contain multiple logical drives. This allows for a total of up to three primary partitions and potentially many logical drives within the extended partition.
This depends on the age of the kernel being used, the type of drive, and the software used to partition the drive. Older Linux systems had a limit of 63 partitions for IDE drives and 15 for SCSI. Kernels before around 2.6.28.5 that used libATA limited all drives to 15 partitions. Experimentation with more recent kernels indicates a limit around 130 partitions per drive. Many partitioning programs available for Linux are still limited to 63 partitions or less.
4 partitions
Due to limitations imposed by DOS back in the '80s, ATA (the proper name for ide) and SATA drives can only hold 4 partitions. To work around this, extended partitions were invented. Extended partitions can hold 4 more partitions, any of which can be more extended partitions. Thus the number of partitions is effectively limited by the size of the disk. These limitations aren't imposed by the disk itself, rather the PC architecture. Intel macs, which don't need to maintain compatibility with DOS or old versions of windows use EFI, which allows for 128 primary partitions.
Ther can only be one Extended Partition per hard drive
none
four primary partitions
four primary partitions
four primary
Partitions are not something that are the same from drive to drive, or from computer to computer. Partitions are created by the user from unused hard drive space, and have no set size, although there is a relatively small minimum. This means that even one one disk, a user can create literally dozens, if not hundreds.
IDE stand for Integrated Drive Electronics.
Disk Druid Partitions is a program that partitions your hard drive for you.