> For the complete documentation index, see [llms.txt](https://philipzheng.gitbook.io/docker_practice/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://philipzheng.gitbook.io/docker_practice/image.md).

# 映像檔

在之前的介紹中，我們知道映像檔是 Docker 的三大元件之一。

Docker 在執行容器前需要本地端存在對應的映像檔，如果映像檔不存在本地端，Docker 會從映像檔倉庫下載（預設是 Docker Hub 公共註冊伺服器中的倉庫）。

本章將介紹更多關於映像檔的內容，包括：

* 從倉庫取得映像檔；
* 管理本地主機上的映像檔；
* 介紹映像檔實作的基本原理


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