Convertir html balise textarea de texte riche

J'utilise PHP pour remplir un textarea:

<textarea text-input" id="Desc" rows="15" wrap="soft" name="Desc"><?php echo $Desc; ?></textarea> 

mais le textarea est de montrer les balises HTML, ce qui je ne veux pas.

<b>Analog And Digital System</b><br />
<b>Analog System:</b><br />
A string tied to a doorknob would be an analog system. They have a value that changes steadily over time and can have any one of an infinite set of values in a range. If you put a measuring stick or ruler at a specific point along the string, you can measure the string's value every so many seconds at that point. When you watch it move, you will see it moves constantly. It doesn't instantly jump up and down the ruler. <br />
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<b>Digital System:</b><br />
A digital system would be to flick the light switch on and off. There's no 'in between' values, unlike our string. If the switch you are using is not a dimmer switch, then the light is either on, or off. In this case, the transmitter is the light bulb, the media is the air, and the receiver is your eye. This would be a digital system.<br />

Fondamentalement, ce que je veux faire est de convertir <b> balises pour mettre le contenu en gras et <br> balises de nouvelles lignes.

Je veux le faire sans l'aide de n'importe quel éditeur.

InformationsquelleAutor SmartDev | 2013-07-22