A Partition is a logical subdivision of a hard disk into smaller chunks. The partition table is the record of the partitions on a hard disk. There are two types of partition tables. The Master Partition Table forms part of the MBR, and can carry details of only four partitions. The need for more than four partitions was met by allowing the creation of an Extended Partition Table, which could contain an unlimited number of partition entries (though the letters in the alphabet limits this number to 24). The Master Partition Table contains a reference to the Extended Partition Table.