From the users manual for GNU parted:
start and end are the offset from the beginning of the disk, that is, the “distance” from the start of the disk.
This is also implied if not outright explained when you
print the current partition table in the parted interface. Check the column heads in the table:
Model: VMware Virtual disk (scsi)
Disk /dev/sda: 53.7GB
Sector size (logical/physical): 512B/512B
Partition Table: msdos
Number Start End Size Type File system Flags
1 1049kB 1075MB 1074MB primary ext4 boot
2 1075MB 53.7GB 52.6GB primary lvm
The start value indicates where you want the new partition to begin. It can be specified in several ways -- an absolute value for size/space, a percentage of the disk size, etc. -- and is measured from the beginning of the disk.