The TinyMCE rich-text editor is enabled by default in textarea fields where you have to encode/input your content.

TinyMCE allows you to format your post without manually inserting HTML codes.

You can turn TinyMCE on or off by default in the edit/account settings of your "my account" page. If you have disabled TinyMCE by default, you can enable it by clicking on the enable rich-text link at the bottom of the textarea.

However, you can always turn off TinyMCE anytime and manually format your post with HTML codes by following the rich-text editing instructions beneath the text area.