The default registry is Docker Hub - using the domain docker.io, and the default image tag is latest.
So kiamol/ch05-pi is the short form of docker.io/kiamol/ch05-pi:latest:
docker pull kiamol/ch05-pi
docker pull docker.io/kiamol/ch05-pi:latest
Check the image list and you'll only see one - these aren't aliases, they're just different froms of the same name:
docker image ls kiamol/ch05-pi
Be wary of using
latestimages - it's a confusing name because it might not be the latest version.
For other registries you need to include the domain in the reference - so images on MCR need to be prefixed with mcr.microsoft.com/:
docker pull mcr.microsoft.com/dotnet/runtime:5.0
Back to the exercises.