diff -r 6c31e66412ee -r fedb77300c7f data/dictionary.xml
--- a/data/dictionary.xml	Sun Aug 18 14:48:40 2013 +0200
+++ b/data/dictionary.xml	Sun Aug 18 16:50:09 2013 +0200
@@ -1324,7 +1324,15 @@
 	<concept>
 		<term abbreviation="VCS" completeForm="version control system" language="en"/>
 		<term abbreviation="RCS" completeForm="revision control system" language="en"/>
-		<explanation language="en"><text></text></explanation>
+		<explanation language="en">
+			<text>
+				a software tool used for management of changes in documents;
+				often is used for managing source code and other artifacts (like documentation or analytic models) created during software development;
+				VCS tracks versions of particular files or changesets, branches, tags (named revisions);
+				examples of traditional centralized VCS: SCCS, RCS, CVS or SVN (quite modern but centralized);
+				nowadays are very popular decentralized systems (DVCS)
+			</text>
+		</explanation>
 		<tag>computer</tag>
 	</concept>
 	<concept>