The RadRichTextEditor allows you to choose between several layout modes.
When using the paged mode, the content of the edited document is divided into pages. The size and layout of each page are defined by the DefaultPageLayoutSettings property of RadDocument and specifically - the Width and Height properties of the PageLayoutSettings object.
Next, the margins of the control in a page are specified by the PageMargin property of each Section.
In Paged mode, resizing a RadRichTextEditor will not affect the document layout but scroll bars will appear if the document does not fit in the view.
In Flow layout mode, the document content is not divided into pages. Instead the whole content is displayed as in a TextBox or RichTextBox. This layout option resembles MS Word’s Web-Layout mode. The width of the document is the same as that of the RadRichTextEditor and changing the control’s width will also resize the content of the document.
The FlowNoWrap layout mode is similar to the Flow layout mode, but it doesn't allow the text in the separate paragraphs to get wrapped when the free space gets exceeded. Instead a horizontal scroll bar will appear.