What is the difference between save and export in Docker? - Stack Overflow

The short answer is:

• save will fetch an image : for a VM or a physical server, that would be the installation .ISO image or disk. The base operating system.

  It will pack the layers and metadata of all the chain required to build the image. You can then load this "saved" images chain into another docker instance and create containers from these images.

• export will fetch the whole container : like a snapshot of a regular VM. Saves the OS of course, but also any change you made, any data file written during the container life. This one is more like a traditional backup.

  It will give you a flat .tar archive containing the filesystem of your container.

Edit : as my explanation may still lead to confusion, I think that it is important to understand that one of these commands works with containers, while the other works with images.

• An image has to be considered as 'dead' or immutable, starting 0 or 1000 containers from it won't alter a single byte. That's why I made a comparison with a system install ISO earlier. It's maybe even closer to a live-CD.

• A container "boots" the image and adds an additional layer on top of it. This layer stores any change on the container (created/changed/removed files...).

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