If I execute lsblk -p command, the following is the output :
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
/dev/loop0 7:0 0 99,4M 1 loop /snap/core/11606
/dev/loop1 7:1 0 4K 1 loop /snap/bare/5
/dev/loop2 7:2 0 55,5M 1 loop /snap/core18/1988
/dev/loop3 7:3 0 219M 1 loop /snap/gnome-3-34-1804/66
/dev/loop4 7:4 0 219M 1 loop /snap/gnome-3-34-1804/72
/dev/loop5 7:5 0 99,3M 1 loop /snap/core/11743
/dev/loop6 7:6 0 55,4M 1 loop /snap/core18/2128
/dev/loop7 7:7 0 131,6M 1 loop /snap/docker/796
/dev/loop8 7:8 0 242,4M 1 loop /snap/gnome-3-38-2004/76
/dev/loop9 7:9 0 51M 1 loop /snap/snap-store/547
/dev/loop10 7:10 0 32,3M 1 loop /snap/snapd/13170
/dev/loop11 7:11 0 165M 1 loop /snap/postman/144
/dev/loop12 7:12 0 32,3M 1 loop /snap/snapd/12883
/dev/loop13 7:13 0 65,1M 1 loop /snap/gtk-common-themes/1515
/dev/loop14 7:14 0 88,1M 1 loop /snap/remmina/5028
/dev/loop15 7:15 0 102,3M 1 loop /snap/remmina/5070
/dev/loop16 7:16 0 51M 1 loop /snap/snap-store/518
/dev/loop17 7:17 0 65,2M 1 loop /snap/gtk-common-themes/1519
/dev/loop18 7:18 0 10,9M 1 loop /snap/ncspot/141
/dev/loop19 7:19 0 168,1M 1 loop /snap/postman/147
/dev/loop20 7:20 0 61,8M 1 loop /snap/core20/1081
/dev/loop21 7:21 0 4,5M 1 loop /snap/spt/275
/dev/nvme0n1 259:0 0 477G 0 disk
├─/dev/nvme0n1p1 259:1 0 300M 0 part /boot/efi
├─/dev/nvme0n1p2 259:2 0 128M 0 part
├─/dev/nvme0n1p3 259:3 0 312,1G 0 part
├─/dev/nvme0n1p4 259:4 0 900M 0 part
├─/dev/nvme0n1p5 259:5 0 17G 0 part
├─/dev/nvme0n1p6 259:6 0 9,6G 0 part /home
├─/dev/nvme0n1p7 259:7 0 3,8G 0 part [SWAP]
└─/dev/nvme0n1p8 259:8 0 111,8G 0 part /
This article mentions that the number in MAJ:MIN column are the numbers used by the kernel to internally identify the devices, the first number specifying the device type (8 for example, is used for SCSI disks). Also, one of the answers on this question unix stack exchange mentions this reference that shows two columns, the left one (i.e 1 block, 2 char, 2 block, etc and the right column that shows the description (i.e memory devices, RAM disk, etc.
From my lsblk -p output above, I have major number 7 and 259. What does that mean? The only number 259 and 7 that I found from this documentation only this text :
259 block Block Extended Major
Used dynamically to hold additional partition minor
numbers and allow large numbers of partitions per device
7 char Virtual console capture devices
0 = /dev/vcs Current vc text (glyph) contents
1 = /dev/vcs1 tty1 text (glyph) contents
...
63 = /dev/vcs63 tty63 text (glyph) contents
64 = /dev/vcsu Current vc text (unicode) contents
65 = /dev/vcsu1 tty1 text (unicode) contents
...
127 = /dev/vcsu63 tty63 text (unicode) contents
128 = /dev/vcsa Current vc text/attribute (glyph) contents
129 = /dev/vcsa1 tty1 text/attribute (glyph) contents
...
191 = /dev/vcsa63 tty63 text/attribute (glyph) contents
NOTE: These devices permit both read and write access.
