How to: 2. Managing Container Images
A docker image consist of layers, and each [image layer](https://vsupalov.com/docker-image-layers/) is its own image. An image layer is a change on an image - every command (FROM, RUN, COPY, etc.) in your Dockerfile (aka Containerfile by OCI) causes a change, thus creating a new layer. It is recommended reduce your image layers as best possible, e.g. replace multiple `RUN` commands with "command chaining" `apt update && apt upgrade -y`.

> A name can be assigned to an image by "tagging" the image. This is often used to identify the image version and/or registry.

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