testdisk output start/end explanation

Question

What do the 3 columns for start and end stand for?
What's the difference between the last two listed partitions?

TestDisk 7.0, Data Recovery Utility, April 2015
Christophe GRENIER <[e-mail]>
http://www.cgsecurity.org

Disk /dev/sda - 120 GB / 111 GiB - CHS 14593 255 63
     Partition               Start        End    Size in sectors
D HPFS - NTFS              0   1  1  1800 254 62   28933002
D HPFS - NTFS              0   1  2  1800 254 63   28933001
D HPFS - NTFS           1800 254 63  3601 253 63      96390
D HPFS - NTFS           1807   0  1 31129 254 63  471073995
D HPFS - NTFS           1807   0  3 31129 254 63  471073993






Structure: Ok.  Use Up/Down Arrow keys to select partition.
Use LEFT/RIGHT Arrow keys to CHANGE partition characteristics:
*=Primary bootable  P=Primary  L=Logical  E=Extended  D=Deleted
Keys A: add partition, L: load backup, T: change type, P: list files,
     ENTER: to continue
NTFS, blocksize=4096, 14 GB / 13 GiB

Answer 1

What do the 3 columns for start and end stand for?

That's the CHS (Cylinder-head-sector) addressing. From Wikipedia:

CHS addressing is the process of identifying individual sectors on a disk by their position in a track, where the track is determined by the head and cylinder numbers. The terms are explained bottom up, for disk addressing the sector is the smallest unit.

Keep in mind that, as written in the article above, «CHS values no longer have a direct physical relationship to the data stored on modern storage media except for floppy disks» however they are still used in many tools as a standard addressing format.

What's the difference between the last two listed partitions?

The latter is 2 sectors smaller than the former.