急!!! <FTB:FreeTextBox></FTB:FreeTextBox>

小弟有一事不明，请高手指教：<FTB:FreeTextBox
 language="zh-cn"
 id="newsContent" 
 runat="server" 
 Width="500px" 
 BackColor="158, 190, 245"
 GutterBackColor="129, 169, 226"
 ToolbarStyleConfiguration="OfficeXP"
 ToolbarLayout="ParagraphMenu,FontFacesMenu,FontSizesMenu,FontForeColorsMenu|Bold,Italic,Underline,Strikethrough;Superscript,Subscript,RemoveFormat|JustifyLeft,JustifyRight,JustifyCenter,JustifyFull;BulletedList,NumberedList,Indent,Outdent;CreateLink,Unlink,InsertImage,InsertRule|Cut,Copy,Paste;Undo,Redo"
 SupportFolder="~/WebComponet/Resource/RichTextBox/">
</FTB:FreeTextBox>此程序段是什么意思？
<FTB:FreeTextBox></FTB:FreeTextBox>指的是什么？
除<FTB:FreeTextBox></FTB:FreeTextBox>外还有哪些？小弟初学，请尽量详解！
谢谢!!!