- control group tree. Those processes are part of different units,
- usually <literal>.service</literal> units (see
- <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>).
+ control group tree. Units that manage processes (primarilly scope
+ and service units) may be assigned to a specific slice. For each
+ slice certain resource limits may the be set, that apply to all
+ processes of all units contained in that slice. Slices are
+ organized hierarchially in a tree. The name of the slice encodes
+ the location in the tree. The name consists of a "-" separated
+ series of names, which describes the path to the slice from the
+ root slice. The root slice is named,
+ <filename>-.slice</filename>. Example:
+ <filename>foo-bar.slice</filename> is a slice that is located
+ within <filename>foo.slice</filename>, which in turn is located in
+ the root slice <filename>-.slice</filename>.