Blocks and Inserts - Introduction to AutoCAD 2011: 2D and 3D Design - page 183

Notes about the DesignCenter palette
1. As with other palettes, the DesignCenter palette can be resized by
dragging the palette to a new size from its edges or corners.
2. Clicks on one of the three icons at the top-right corner of the palette
(Fig. 9.11) have the following results**.
Fig. 9.11 The icons at the top of the DesignCenter palette
Tree View Toggle - changes from showing two areas - a Folder List
and icons of the blocks within a fi le - to a single area showing the
block icons ( Fig. 9.12 ).
Fig. 9.12 The results of a click on Tree View Toggle
Preview - a click on the icon opens a small area at the base of the
palette open showing an enlarged view of the selected block icon.
Description - a click on the icon opens another small area with a
description of the block.
A block is a single object no matter from how many objects it was
originally constructed. This enables a block to be dragged about the
drawing area as a single object.