There are commands in AutoCAD that do not have a shortened alias for easy use. An Alias is a one-to-three letter shortened version of a command that saves time typing in the command. For example, the alias L is the same as the command LINE .

Luckily, for those who have a full version of AutoCAD and have the Express Tools loaded have a command alias generator/editor. To find it in the ribbon:
Express Tools tab/ribbon > Tools panel > Command Alias button
command = ALIASEDIT

This editor is great because it is fast and prevents you from messing up your acad.pgp file. For those who do not know what the acad.pgp file is. It is the AutoCAD Program Perameters file where command and command aliases are stored. For those who know what they are doing, you can find and edit this file as needed. But if you edit this file while AutoCAD is running, you either have to restart AutoCAD or use the REINIT command for AutoCAD to take on the new changes. Well, with this handy-dandy Alias Editor, it does all of that work for you and makes sure that you don’t duplicate an alias that is in use. It’s also a great way to get familiar with what commands have what alias….

In the Alias Editor dialog box:

Click the ADD button – a new dialog will appear
Enter the new alias in the upper text box – for this example (2011) enter SS
Enter the Command that will be tied to the new alias in the lower text box. – for this example (2011) enter SELECTSIMILAR.
click OK and confirm the change.
Congratulations on making your alias.

In AutoCAD 2011, there is a great new command (among many) called SELECTSIMILAR.
There are a couple of ways to use this command. If you select an object – let’s say a line in the drawing and then right-click, you will see this new option in the right-click menu. If you select it, it will select all of the lines that are on that layer that are in the drawing. If you select a line on one layer and another line on a different layer and even a circle that is on another layer, then right-click, you will notice that SELECT SIMILAR is still there. If you select it now, it will select all of the lines on those two layers and all circles on the third layer in the drawing.

This is an easy way to filter your selection. But wait – there’s more…
We created a new alias – now let’s use it.
Enter the new alias SS <enter> at the command line and look at what you see in the command line. It says “Select objects or [SEttings]:”
Type in SE <enter> at the command line and a little dialog will appear that allows you to select even more settings of objects besides the layer.
If you like the Quick Select command, you’ll really appreciate this one as well