diff -r 0d307e7538b0 -r 6daaf1c6fede data/dictionary.xml
--- a/data/dictionary.xml	Mon Aug 19 21:35:32 2013 +0200
+++ b/data/dictionary.xml	Mon Aug 19 21:42:46 2013 +0200
@@ -1344,7 +1344,13 @@
 	<concept>
 		<term abbreviation="" completeForm="keep alive" language="en"/>
 		<term abbreviation="" completeForm="keep-alive" language="en"/>
-		<explanation language="en"><text></text></explanation>
+		<explanation language="en">
+			<text>
+				a packet or message or command without useful content
+				which is sent in order to avoid closing the connection (time out) and to check, it is still working;
+				in HTTP this term means persistent connection
+			</text>
+		</explanation>
 		<tag>computer</tag>
 	</concept>
 	<concept>