How to build a image from Dockerfile

1. Build a docker image by Dockerfile  (without file extension) 

$ docker build .

2. Build image by a Dockfile with filepath

$ docker build -f /path/to/a/Dockerfile .

3.Build an image with tag name 

$ docker build -t shykes/myapp .
# or build duplicated images 
$ docker build -t shykes/myapp:1.0.2 -t shykes/myapp:latest .

Build cache is only used from images that have a local parent chain. This means that these images were created by previous builds or the whole chain of images was loaded with docker load. If you wish to use build cache of a specific image you can specify it with --cache-from option. Images specified with --cache-from do not need to have a parent chain and may be pulled from other registries.

BuildKit
Starting with version 18.09, Docker supports a new backend for executing your builds that is provided by the moby/buildkit project. The BuildKit backend provides many benefits compared to the old implementation. For example, BuildKit can:
Detect and skip executing unused build stages
Parallelize building independent build stages
Incrementally transfer only the changed files in your build context between builds
Detect and skip transferring unused files in your build context
Use external Dockerfile implementations with many new features
Avoid side-effects with rest of the API (intermediate images and containers)
Prioritize your build cache for automatic pruning
To use the BuildKit backend, you need to set an environment variable DOCKER_BUILDKIT=1 on the CLI before invoking docker build.

4. Docker Languages Type:

# Comment
INSTRUCTION arguments

5. Go into the container of docker.

docker exec -it  <ContainerID> /bin/bash

*on alpine, no bash but sh. /bin/sh will be ok

6. docker -v 

docker run -it -v c:\Data:c:\shareddata microsoft/windowsservercore powershell