You can use block libraries and tool palettes to organize and manage blocks.
A block library is a collection of block definitions stored in a single drawing file. You can use block libraries supplied by Autodesk or other vendors or create your own.
Block definitions from block libraries can be inserted individually into any drawing. Block library drawings are not different from other drawing files except in how they are used.
You can also create a visual reference of each block definition by inserting it in the block library drawing along with descriptive text that provides the block name, the date of creation, the date of the last modification, and any special instructions or conventions.
Use the Blocks palette or DesignCenter to view and copy block definitions individually from block library drawings or from any existing drawing to your current drawing.
The Tool Palettes window is recommended when you need to organize a large number of blocks into a custom tabbed palette. When you define a block in the block library drawing, you can also include a short description of the block in the Block dialog box. The description displays when you hover over the block in the Tool palettes window.