TLDR; At fundamental level, the idea is that most VMs don't change much to their large images so you can lazily only work with diffs. The copy-on-write allows b

TLDR; At fundamental level, the idea is that most VMs don't change much to their large images so you can lazily only work with diffs. The copy-on-write allows blocks of your new file points to blocks of original and maintain diff of blocks that get changed. Overall great article!