containers/org.eclipse.linuxtools.docker.editor/assets/additional-info/FROM.html

<p>
<b>FROM</b> sets the base image starting from which the image is built.
</p>
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<p>
<pre>
FROM image
</pre>
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<pre>
FROM image:tag
<pre>
<br/>
FROM image@digest
</pre>
</p>
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<p>
<b>FROM</b> must be the first non-comment instruction in the Dockerfile 
</p>