A GPT, or GUID Partition Table, is a type of partitioning scheme used on a hard drive or other storage device. It is a more modern alternative to the older MBR (Master Boot Record) partitioning scheme, and allows for larger storage capacities and more partitions on a single device.
A GPT is made up of a series of partition entries, each of which contains information about a partition on the storage device. This information includes the partition's type, size, and location on the device.
The size of a GPT is determined by the number of partition entries it contains. A GPT can contain up to 128 partition entries, each of which is 16 bytes in size. This means that the maximum size of a GPT is 2,048 bytes (128 x 16).
In addition to the partition entries, a GPT also contains a primary and secondary header, which contain information about the GPT itself. The primary header contains a copy of the partition entries and is located at the beginning of the GPT, while the secondary header is a backup copy located at the end of the GPT.
One advantage of using a GPT is that it allows for larger storage capacities. While an MBR partition scheme is limited to 2 TB, a GPT can support devices up to 9.4 zettabytes in size. A GPT is also more resilient to corruption, as it has a backup copy of the partition entries in the secondary header.
In conclusion, a GPT is a type of partitioning scheme used on storage devices that allows for larger storage capacities and more partitions. Its size is determined by the number of partition entries it contains, and it also includes a primary and secondary header.
