Introduction
Why did Docker decide to go with a whale for their logo? Apparently to express its product’s values of expedition, automation, encapsulation and simplification. As they explain “the whale is carrying a stack of containers on its way to deliver those to you”.

下面改编自 官方教程. 总得来说, Dockerfile 类似脚本, 记录了构建镜像 (文件) 的指令. 运行着的镜像称为容器 (类似进程). 而 docker-compose.yml 记录了运行镜像的参数配置 (类似用 shell 脚本记录命令行).