Match() String help

Hi all!
I need some help with this code:

<script>
str = new String("Hello World")
document.write(str.match('Hello').fontcolor("blue"))
</script>

I want the word "Hello" of the string to have a blue color. Not the hole string JUST the "Hello" word.:confused: :confused: :confused: :confused:

With the following CSS.hello{
color: blue;
}you can write the script like this:var
str='Hello World';
alert(str.replace(/Hello/g,'<span class="hello">$&</span>'));

How i do it if i have the "Hello" word in a textarea.

<textarea>
Hello World
</textarea>

Help Please