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<chapter id="chap-Metadata">
	<title>Upstream Metadata</title>
	<para>
		AppStream allows upstream projects to define metadata about the components they provide using small XML files,
		metainfo files,	which get installed into locations on the client system and are used by distributors to enhance their
		metadata.
	</para>
	<para>
		A "component" is a piece of software, like an application, a library, a font or a codec. For several components, especially
		those which are shown in software-centers, we provide specialized metainfo files to define specific properties and data of these components.
		For example, applications and fonts support screenshots, while codecs don't.
	</para>
	<para>
		All metainfo files need to contain a minimal amount of information, defined in the "Generic Component" section, which also describes some optional
		elements which can be used.
		Specialized components might require more information to be complete and valid.
	</para>
	<para>
		The XML in metainfo files does not need any XML namespace, and adding one should generally be avoided.
		If you want to use a namespace though (maybe in case you want to embed the data in other contexts), the xmlns
		should be <code>https://specifications.freedesktop.org/metainfo/1.0</code>.
	</para>

	<xi:include href="metainfo-component.xml" xmlns:xi="http://www.w3.org/2001/XInclude" />
	<xi:include href="releases-data.xml" xmlns:xi="http://www.w3.org/2001/XInclude" />

	<xi:include href="metainfo-desktopapp.xml" xmlns:xi="http://www.w3.org/2001/XInclude" />
	<xi:include href="metainfo-consoleapp.xml" xmlns:xi="http://www.w3.org/2001/XInclude" />
	<xi:include href="metainfo-webapp.xml" xmlns:xi="http://www.w3.org/2001/XInclude" />
	<xi:include href="metainfo-service.xml" xmlns:xi="http://www.w3.org/2001/XInclude" />
	<xi:include href="metainfo-addon.xml" xmlns:xi="http://www.w3.org/2001/XInclude" />
	<xi:include href="metainfo-font.xml" xmlns:xi="http://www.w3.org/2001/XInclude" />
	<xi:include href="metainfo-icontheme.xml" xmlns:xi="http://www.w3.org/2001/XInclude" />
	<xi:include href="metainfo-codec.xml" xmlns:xi="http://www.w3.org/2001/XInclude" />
	<xi:include href="metainfo-inputmethod.xml" xmlns:xi="http://www.w3.org/2001/XInclude" />
	<xi:include href="metainfo-firmware.xml" xmlns:xi="http://www.w3.org/2001/XInclude" />
	<xi:include href="metainfo-driver.xml" xmlns:xi="http://www.w3.org/2001/XInclude" />
	<xi:include href="metainfo-localization.xml" xmlns:xi="http://www.w3.org/2001/XInclude" />
	<xi:include href="metainfo-repository.xml" xmlns:xi="http://www.w3.org/2001/XInclude" />
	<xi:include href="metainfo-operatingsystem.xml" xmlns:xi="http://www.w3.org/2001/XInclude" />
	<xi:include href="metainfo-runtime.xml" xmlns:xi="http://www.w3.org/2001/XInclude" />

</chapter>
