For MBR-style partition, each partition will have one Partition Type ID.
System can tell the types of partitions by the ID, the following is the most frequently used Type ID.
0x0B FAT32, used by DOS & Win95
0x0C FAT32 using LBA mode to access to FAT32 partition
0x04 FAT16, less than 32 MB
0x06 FAT16, greater than 32 MB
0x0E FAT16 using LBA mode to access to FAT16 partition
By changing the partition type ID, users can prevent the system using or initializing partitions.