What is GPT (GUID Partition Table)?

What is GPT (GUID Partition Table)?: Short for GUID Partition Table, GPT is a part of the EFI standard that defines the layout of the partition table on a hard drive. GPT is meant as a replacement to hard drives using a MBR partition table, which have a 2.20TB size limitation and extends upon UEFI. Using GPT a drive could support between 8 and 9.4 ZB depending on the sector size.