+ <refsect1>
+ <title>Special Slice Units</title>
+
+ <para>There are four <literal>.slice</literal> units
+ which form the basis of the hierarchy for assignment
+ of resources for services, users, and virtual machines
+ or containers.</para>
+
+ <variablelist>
+ <varlistentry>
+ <term><filename>-.slice</filename></term>
+ <listitem>
+ <para>The root slice is the
+ root of the hierarchy. It
+ usually does not contain units
+ directly, but may be used to
+ set defaults for the whole
+ tree.</para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><filename>system.slice</filename></term>
+ <listitem>
+ <para>By default, all services
+ services started by
+ <command>systemd</command> are
+ found in this slice.</para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><filename>user.slice</filename></term>
+ <listitem>
+ <para>By default, all user
+ processes and services started
+ on behalf of the user,
+ including the per-user systemd
+ instance are found in this
+ slice.</para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><filename>machine.slice</filename></term>
+ <listitem>
+ <para>By defalt, all virtual
+ machines and containers
+ registered with
+ <command>systemd-machined</command>
+ are found in this slice.
+ </para>
+ </listitem>
+ </varlistentry>
+ </variablelist>
+ </refsect1>
+