1.1 --- a/data/dictionary.xml	Tue Aug 13 18:00:06 2013 +0200
     1.2 +++ b/data/dictionary.xml	Tue Aug 13 20:31:34 2013 +0200
     1.3 @@ -1612,7 +1612,15 @@
     1.4  	</concept>
     1.5  	<concept>
     1.6  		<term abbreviation="MAC" completeForm="media access control" language="en"/>
     1.7 -		<explanation language="en"><text></text></explanation>
     1.8 +		<explanation language="en">
     1.9 +			<text>
    1.10 +				a data communication protocol, a sublayer of the layer 2 in OSI model (data link layer); 
    1.11 +				a MAC address is a unique identifier of an network interface – used for IEEE 802 networks including Ethernet;
    1.12 +				they are assigned by the manufacturer of the card and stored in the hardware (can be often changed by the software);
    1.13 +				there are three numbering namespaces: MAC-48, EUI-48 and EUI-64;
    1.14 +				the address has 6 or 8 bytes and they are usually written in HEX, octets separated by : (a colon)
    1.15 +			</text>
    1.16 +		</explanation>
    1.17  		<tag>computer</tag>
    1.18  	</concept>
    1.19  	<concept>