Dockerの「無効な参照形式」エラーのトラブルシューティング

# Introduction

When working with Docker, encountering the "invalid reference format" error can be a common roadblock for beginners. This error typically appears when Docker cannot correctly interpret the name or format of an image you are trying to work with. In this lab, you will learn about Docker image naming conventions, how to identify this specific error, and implement practical solutions to resolve it.

By the end of this lab, you will understand the Docker image reference format, be able to diagnose common causes of the "invalid reference format" error, and gain practical experience in resolving these issues.