With lsblk you can see that partition types (PARTTYPE) in the GUID Partition Table (GPT) are defined by UUIDs, so that's probably where a lot of the confusion comes from. The MBR (Master Boot Record) used types with an integer value, like 0x83 for Linux or 0x0C for FAT32 LBA. On GPT those partitions use a UUID, i.e. Linux is now 0FC63DAF-8483-4772-8E79-3D69D8477DE4 (or a newer one, like the special FreeDesktop.org partition types for systemd automount to work) and FAT32 is EBD0A0A2-B9E5-4433-87C0-68B6B72699C7, but like with MBR partitions, every FAT32 partition (if there are more) (may) have the same PARTTYPE. Then, additionally, every partition has a unique UUID that is randomly given at the time of creation: PARTUUID. And lastly, every file system has a UUID as well, UUID. To show them with lsblk:

root #lsblk -o +PARTTYPE,PARTUUID,UUID

Additionally to this, every GUID Partition Table itself also has a unique UUID, PTUUID:

root #lsblk -o +PTUUID

If you have only one internal disk, and thus only one GPT, you'll see the same PTUUID for every partition. I have two disks, so I see two unique PTUUIDs, one for every drive that has a GPT. <a href="/wiki/User:Luttztfz" title="User:Luttztfz">Luttztfz</a> (<a href="/index.php?title=User_talk:Luttztfz&action=edit&redlink=1" class="new" title="User talk:Luttztfz (page does not exist)">talk</a>) 14:00, 11 June 2024 (UTC)