What Is A Partition?
As you can probably guess by breaking down the word
partition, it's a 'part' or section of the hard disk,
although that's a bit misleading because 'part' tends to
indicate that a partition is less than 100% of the drive.
Although a partition 'can' be less than 100% of the space
available on a drive it doesn't have to be less. As a matter
of fact a hard drive can exist perfectly well on a system
without any partition(s) on it whatsoever; it just won't be
of any value for accessing and storing data. I think it's a
bit more accurate to look at partitions as
defining a certain area or amount of space on a hard drive,
be it 1 or 100% of the drives total capacity.
Partition Types
Depending on type of system
and what operating system is being used there are many
different types of partitions, but since this site deals
with XP it's most likely you'll be dealing with two types of
partitions; Primary and Extended. Depending on who you ask,
some people consider logical drives as another type of
partition. To me, this is more a case of semantics than
anything else, but I've included Logical Drives in this
section.
Primary Partition
- A partition that is used to start an operating system,
although you can use primary partitions that don't
contain the operating system.
Look at the color coded key at the bottom of Fig. 01 and
you'll see that Primary partitions are denoted by the
dark blue color.
- There can be up to a maximum of four primary partitions
on a single basic disk.
- The Primary partitions do not have to come before
Extended partitions as shown on Disk 0.
- A drive is not required to have any Primary
partitions as shown by Disk 1
- CD-ROM 1, while it does
contain a blank CD, is not shown as containing a
partition because there is no data contained on the CD.
Fig. 01
Extended Partition
- A partition that can be sub-divided into logical
drives. Look at the color coded key at the bottom of
Fig. 01 and you'll see that Extended partitions are denoted
by the dark green color.
- An extended partition is not formatted or
assigned a drive letter.
- It's essentially a container
for logical drives that are formatted and assigned drive
letters. Disk 0 and 1 contain extended
partitions that have a green band surrounding the logical
drives (discussed below) that have been created in the
extended partition.
Logical Drive - A
logical drive is created within an extended partition.
Look at the color coded key at the bottom of Fig. 01 and
you'll see that Logical drives are denoted by the lighter,
bright
blue color.
- An "unlimited" number
of logical drives may be created in
an extended partition, formatted and assigned drive
letters. Unlimited is another misleading term used in
conjunction with logical drives. The reality is you're
limited by the number of available drive letters and the
amount of hard drive space available for creating
drives. In Fig. 01, Disk 1 has two logical
drives, F and G, identified by the bright blue color and contained
within the extended partition. More Logical drives could
be created in the Free Space until you either ran out of
drive letters or the Free Space was exhausted.
- Disk 1 and 2 also contain Unallocated space that isn't
assigned to either a primary or extended partition. I'll
deal with unallocated space later in the article.
System and Boot Partitions
This seems like as good a time as any for a brief
discussion of System and Boot partitions. In almost every
case where I've attempted to explain the difference between
System and Boot partitions people have walked away shaking
their heads because it just doesn't make any sense,
but I'll give it another try. Here we go;
- Whenever a computer system is started, either from a
cold boot using the power switch or a warm boot such as
restarting the system from within Windows, there are
certain files needed to boot (start) the computer. These
boot files reside on the System partition.
- Once the boot files have been accessed and performed
their function, the system files (the files that
comprise the XP operating system) are accessed to
complete the system start. The system files reside on
the Boot partition.
If you just accept these two statements are true then
everything will be fine. I know it makes no sense and seems
to defy logic, but it's true.
The boot files reside on the System partition
--- The system files reside on the Boot partition
Fig. 02
Look at Fig. 02 and you'll see C: is
designated as the System partition. There is no designated
Boot partition. In most cases this is the standard setup and
there won't be a separate Boot partition
designated.
Look at Fig. 03 and you'll see C: is
designated as the System partition and I: is designated as
the Boot partition. The boot files are located on partition
C: and the system files (the XP operating system) are
installed on the I partition.
Both screen captures are of the identical
system so why does one have the Boot partition uniquely
identified? The answer is because there are two operating
systems installed on the same machine, or what is often
called a dual boot setup. Windows XP is installed on drive C: and
Windows XP is also installed on drive I:. When the system is
set to boot from the operating system installed on partition
C: the system and boot files reside in the same partition so
there is no need for a separate Boot partition designation.
When the system is set to boot from the operating system
installed on partition I: the system and boot files reside
on different partitions so partition I is designated as the
Boot partition.
Fig. 03
There is one more term that you may
occasionally run across and that's Active partition. Any
primary partition that has an operating system installed on
it may be designated as the Active partition simply for the
sake of convenience in making it the System partition.
Active partition and System partition mean the same thing.
Up
What Is A Partition?
One Partition or Multiple Partitions?
Partitioning A Blank Hard Drive During XP Installation
Reassigning Drive Letters
Resizing An Existing Partition On A Single Hard Drive
Creating A Primary Partition In Unallocated Space
Creating An Extended Partition And Logical Drives
Creating Logical Drives In An Extended Partition
Multiple Hard Drive System Partitioning
Converting Basic Disks to Dynamic Disks
|
