Difference between image and snaphot?

Question

Can any one explain what are the differences between image and snapshot in terms of storage.

Answer 1

An image is just that: A complete copy of a block device (or file system or whatever), while a snapshot contains the differences of the device compared to the current state (or some other defined state, e.g. an image).

Answer 2

You give no context, but an image will generally be a complete bit for bit copy of the entire hard drive of a machine, whether virtual or physical. They are normally transportable and are standalone ready to be imported or imaged onto another machine.

A snapshot is a virtualisation technology that relies on delta discs to work efficiently. They are intended for short term use and are useless without all other virtual machine files. There are plenty of resources out there for learning more.