Docker Build Contexts and Caching

When you run Docker build, you specify a path, which is normally just the current directory. It will then copy all of the files from that directory into what's called a Docker builds context. So it's in a way is kind of invisible to you that it's doing that it feels like you're just copying it from your host machine. The reason it does this is because the build might not always be happening on the same machine. You can also create a Docker ignore file to tell Docker build not to copy certain files or directories into your Dockerbuild context.