strange html code to set the type of characters

On a web page i found a very strange html code (see at the en of this
message) to set the type of the characters (like bold, italic, etc.)
and I have 2 question

1) How interpreter this code ?
2) can I use this code to set also the colour and the font used for the
text (like verdana) ? If yes how ?

Thank you in advance for your help

Fabrizio

The strange code (the code that contain "%" like "%3Cb%3ECopenhagen
08/01%3C/b%3E"




<area shape="rect" coords="384,137,448,162"
href="Copenhagen_01/italiano.htm" alt="Copenhagen" title="Copenhagen"
onMouseOver="MM_changeProp('dest1','','src','Copenhagen_01/s1.jpg','IMG');MM_changeProp('dest2','','src','common/bia
nca.gif','IMG');MM_setTextOfLayer('titolo','','%3Cb%3ECopenhagen
08/01%3C/b%3E');MM_setTextOfLayer('descrizione','','%3Ci%3EPrima di
proseguire per la Groenlandia, ho l%27opportunit&amp;#224; di fare un
breve giro nel centro di Copenhagen.%3C/i%3E')"
onMouseOut="MM_setTextOfLayer('descrizione','','%3Ci%3ESpostare il
mouse sulla cartina per selezionare un viaggio.
Ciascun viaggio e%27 indicato con colori
diversi.%3C/i%3E');MM_setTextOfLayer('titolo','','%3Cb%3EMenu dei
viaggi%3C/b%3E');MM_changeProp('dest2','','src','common/bianca.gif','IMG');MM_changeProp('dest1','','src','common/bi
anca.gif','IMG')">