Format text in a <textarea>?

You Can't style the content of a text area separately, you have to use <div>s, or something similar.

Do you Want Something like this:?

http://jsfiddle.net/mekwall/XNkDx/

$('.editable').each(function(){
    this.contentEditable = true;
});

This allows you to edit the content of a div, and it will still look like a textarea,

Bold will now Work.

If you need to customize your textarea, reproduce its behavior using another element (like a DIV) with the contenteditable attribute.

It's more customizable, and a more modern approach, textarea is just for plain text content, not for rich content.

<div id="fake_textarea" contenteditable></div>

The scrollbars can be reproduced with the CSS overflow property.

You can use this fake textarea in a form normally, i.e: if you have to submit its content through POST method, you could do something like(with jQuery):

<input type="hidden" id="fake_textarea_content" name="foobar">

...

$('#your_form').submit(function()
{
  $('#fake_textarea_content').val($('#fake_textarea').html());
});