Why does pvcreate use character devices while vgcreate uses Block devices?

In LVM,
(1) pvcreate uses character devices.
# Pvcreate-F/dev/rdsk/c0t3d0

(2) vgcreate uses Block devices.
# Vgcreate/dev/vg01/dev/DSK/c0t3d0

(3) when creating a file system using newfs, what is the character device used ??
# Newfs-F vxfs/dev/vg01/rmyfs1

(4) The mount command requires a block device file.
# Mount/dev/vg01/myfs1/myfs1

I would like to ask, under what circumstances are character devices and Block devices used ??

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Logical volume management for hard disk resources for HP-UX
HP-UX Management of hard disk storage resources is the use of logical volumes to manage, to clarify the entire mechanism, first to introduce several concepts:

Physical Volume physical volume, called PV: refers to the physical hard disk, a hard disk is a PV

Logical volume group (VG): a VG contains an integer PV, which can be considered as a large hard disk.

Logical volume, called LV: it is equivalent to a logical partition of a large hard disk. a vg can contain several LV.

File System: On the basis of logical volumes, you can create a file system and mount it to a directory. In this way, you can use this hard disk by means of file access.

Of course, you can also directly use LV as a bare device without creating a file system to access data in trunk mode. Many databases use this method to access data.

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Character device, because the disk is reserved

Block device, because you do not need to operate on the reserved area