AutoCAD offers several different options for creating blocks. All produce the same results. The one you pick will depend on your work style and the type of block you are creating.
Copy and paste. This is the simplest method. Just select the entities you want to turn into a block. Right-click and select Copy or Cut from the shortcut menu that appears (or just press <Ctrl>+C or <Ctrl>+X). Right-click again and select Paste as Block (or press <Ctrl>+<Shift>+V). AutoCAD will prompt for the insertion point. If you want to reuse the block or have others use it, other creation methods will give you more control.
Caption: Once you select and copy the objects that make up your block, right-click and select Paste as Block.
Block command. You can use this to convert existing entities in your current drawing. Type Block at the command line. The Block Definition dialog box displays. Here you can name your block and specify a base point (the point that will fall on the insertion point specified when the block is inserted). Under Objects, specify the entities to include in the block. If you click the Retain button, the objects you select will remain as they are in the drawing. Select Convert to Block to convert them to a block. Select Delete to delete them once your block is created. Options under Behavior allow you to make the block annotative, scale it uniformly, and explode it.
Caption: Block Definition dialog box. What you see may vary depending on your version of AutoCAD.
Wblock command. Wblock is short for Write Block. As its name suggests, it creates a new drawing file from the objects you select. The drawing file can then be inserted as a block. This approach is best when you are using block libraries or sharing blocks with other users. Wblock works in much the same way as the Block command. You specify a base point and the objects you want to include in the drawing (note that you can also write the entire drawing as a block). Provide a name and location to store your new drawing.
Caption: Write Block dialog box.
Block Editor. The Block Editor is an environment dedicated to block creation. You will need to use the Block Editor if you want to create dynamic blocks. Launch the Block Editor by typing Bedit at the command line or by selecting Block Editor from the Tools menu. You can also select any block and right-click to bring up a shortcut menu that lists the Block Editor.
When the Block Editor opens, you can either select an existing block to edit or create a new one from scratch. Note: If you’ve already drawn a block using the Block command, check the Open in Block Editor box in the Block Definition dialog box to have the Block Editor open automatically with your new block displayed.
Caption: Create or edit blocks in the Block Editor.
Caption: The Block Editor provides tools for drawing blocks and assigning dynamic properties.
When you’re done, select Save Block to save your block definition or Save As to create one with a new name. The origin (0,0) in the Block Editor represents the insertion point of your block. Move your geometry relative to the origin to change the insertion point.