The pound sign is the sign for a color defined in hex. It tells the computer that you will be referencing a color, and tells it how to handle it. Don't take it out!
For multicolored links (I think you mean escaping the default blue color), you have to set a different style. You can do this with your global CSS, if you are using it, or by just putting a style property in the <a> tag. Like so:
HTML Code:
<a href="http://www.google.com" STYLE="color: #C0C0C0">Visit Google!</a>
This will override the automatic blue rendering and assign the link the color of #C0C0C0, or light gray. Change the latter to whatever you please.