|You can have up to four primary partitions, or up to three primary partitions and 1 extended partition (which is another type of partition), and more than one logical partition within the extended partition. The extended partition is merely a "container" and must have at least one logical partition within it in order for you to be able to store data on it. |
I have one 500gb drive that has 7 partitions
- two primary, one extended, 4 logical partitions within the extended partition - all of those (except the extended partition of course ) are assigned drive letters in Windows, and one small primary FAT partition at the end of the drive space that has no drive letter and does not show up in My Computer (or Computer) or Windows Explorer that is for my third party multi-boot program, BootIt! NG
Brand name computers sometimes have a smaller EISA partition on the original hard drive software installation. It may or may not be required in order for you to be able to use the contents of it when you want to reload the original brand name software installation. It doesn't show up in My Computer (or Computer) or Windows Explorer but it does show up in Disk Management (as an unknown partition type as I recall ??) and when you're using the XP CD to examine the existing partitions on the drive, and when you use a third party "partition manipulation" program to examine the drive.
E.g. On a friend of mine's HP laptop it had a small EISA partition that was used for some music feature and it is not required in order to re-load the original brand name software installation - the partition can be deleted if you don't use the music feature, and the space freed up can be added to another existing partition by using a third party "partition manipulation" program such as the freeware Easeus Partition Master Home Edition.
(You must use a third party program to do that in XP or previous if you don't want to lose the data on the existing partition. Disk Management in Vista and Windows 7 has the ability of being able to add freed up drive space to an existing partition, or re-size partitions smaller or larger, without losing the data on the existing partition, but there is insufficient info about that in it's Help - it's easier to use a third party program to do that.)
The computer came with 3 Recovery CDs - one of them was used to load the software required for the music feature on the EISA partition. The information about how to use the music feature was in the HP User's or Owners manual for the model as I recall. Later on she lost track of where her Recovery CDs were - I ordered a set from HP and it had 2 of the 3 CDs - the one for the music feature was not included. .