Learn about（了解） images & containers（docker核心技术）
Docker Engine（引擎，发动机） provides the core Docker technology that enables images and containers（启用镜像和容器）. As the last step in your installation, you ran the Engine
docker run hello-world command. With this one command, you completed the core tasks to using Engine. The command you ran had three parts.（这个命令包含了3个部分）
A container（集装箱，容器） is a stripped-to-basics version of a Linux operating system. An image is software you load into a container. When you ran the command, the Engine software:(当你运行这个命令时，这个引擎软件：)
checked to see if you had the
downloaded the image from the Docker Hub (more about the hub later)（从Docker中心下载镜像）
loaded the image into the container and “ran” it（将镜像载入到容器并运行它）
Depending on how it was built, an image might run a simple, single command and then exit. This is what
A Docker image, though, is capable（能干的，能胜任的） of much more. （Docker image然而能干的事更多）An image can start software as complex as a database（如数据库一样复杂）, wait for you (or someone else) to add data, store the data for later use, and then wait for the next person.
Who built the
hello-world software image though?（然而谁可以构建镜像image？） In this case（在这个事例中）, Docker did but anyone can. Docker Engine lets people (or companies) create and share software through Docker images. Using Docker Engine, you don’t have to worry about whether your computer can run the software in a Docker image — a Docker container can always run it.
Where to go next（接下来去哪？）
See, that was quick wasn’t it? Now, you are ready to do some really fun stuff（东西，材料） with Docker.（现在，你可以准备去做一些真正有趣的东西了） Go on to the next part（继续下一部分） to find and run the whalesay image.