LVM is a logical volume manager for the Linux kernel that manages disk drives and similar mass-storage devices. Suppose if you have lots of hard drive by this lvm we can combine all the hard drive together and then shrink from it by own choice.
For ex:-we have two hard drive of 40 gb 2.create partition in it 3.then make them physical volume by pvcreate cmd 4.then create volume group volume can be of 80gb 5.then I can shrink any type of volume from volume group 6.then we we have to format shrinked drive by file system by ext3, 4 or any 7.and make mount to make it usable.
Uses of lvm in:-
Database server, company server, home.
Benefits:- Allow you to create larger partitions than you could with a single drive, allow you to add hard drive, shrink drive, or move those from one to other drive.