I noticed that Linux server distros are using LVM as default. What is so good about LVM, and when should I use it? Is there a GUI for managing LVM volumes like GParted, or is it just through the terminal? How is it different from RAID in using multiple drives for one volume?
In addition to those things you can also thin provision lvm volumes which is helpful sometimes and it even has built in caching. It really is just a much more flexible way of using a disk, it is not an an analog for RAID, you would typically use a RAID volume with LVM on top.
Works the other way too, can do a LVM with RAID underneath. I currently use LVM raid 5 with XFS underneath. Though all the news around bcachefs has got me pretty excited to go that route and cut out the LVM middleware.