1.What is wrong with MBR partitioning?

MBR disks support only four partition table entries.and MBR partitioning rules are complex and poorly specified.  An MBR partition is identified by a two-byte field, and coordination is necessary to avoid collision.today there is no single authoritative list of partition identifiers.

2. Why do we need GPT?  GPT disks can grow to a very large size.  The GPT disk partition format is well defined and fully self-identifying

3.What is the GPT format for basic disks?  Basic disks are the storage types most often used with Windows. The term basic disk refers to a disk that contains partitions, such as primary partitions and logical drives, and these in turn are usually formatted with a file system to become a volume for file storage.

4. What is the GPT format for dynamic disks?

Dynamic disks were first introduced with Windows 2000 and provide features that basic disks do not, such as the ability to create volumes that span multiple disks (spanned and striped volumes) and the ability to create fault-tolerant volumes (mirrored and RAID-5 volumes). Like basic disks, dynamic disks can use the MBR or GPT partition styles on systems that support both.

5. Is UEFI required for a GPT disk?

No. GPT disks are self-identifying. All the information needed to interpret the partitioning scheme of a GPT disk is completely contained in structures in specified locations on the physical media.

6. How big can a GPT disk be?

In theory, a GPT disk can be up to 2^64 logical blocks in length. Logical blocks are commonly 512 bytes in size. The maximum partition (and disk) size is a function of the operating system version. Windows XP and the original release of Windows Server 2003 have a limit of 2TB per physical disk, including all partitions. For Windows Server 2003 SP1, Windows XP x64 edition, and later versions, the maximum raw partition of 18 exabytes can be supported. (Windows file systems currently are limited to 256 terabytes each.)

7. How many partitions can a GPT disk have?

The specification allows an almost unlimited number of partitions. However, the Windows implementation restricts this to 128 partitions. The number of partitions is limited by the amount of space reserved for partition entries in the GPT.

8.  Can a disk be both GPT and MBR?

No. However, all GPT disks contain a Protective MBR.

9. What is a Protective MBR?

The Protective MBR, beginning in sector 0, precedes the GPT partition table on the disk. The MBR contains one type 0xEE partition that spans the disk.

10.Can Windows XP x64 read, write, and boot from GPT disks?

Windows XP x64 Edition can use GPT disks for data only.