The command line in AutoCAD 2013 received a face lift or rather acquired a new look and feel. When you start AutoCAD 2013, the command line appears transparent, however when you type or select an option in the command line it becomes opaque.
The command history scrolls up above the active prompt and the number of lines of this history is controllable. Also, the option keywords displayed in the commandline are now clickable. Then, once a command is complete, the command history fades away.
The command history is still accessible by selecting F2 or choosing the arrow at the end of the commandline. Recently used commands can be selected from the menu available at the left end of the commandline.
The commandline can be moved around the drawing area or docked. When docked it resembles the way the commandline looked in previous versions.
The wrench icon at the left end of the commandline launches a menu of commandline settings and the OPTIONS command. If the commandline is not docked, you can control the number of lines of history, the general transparency of the commandline and the mouse-over transparent value.
AutoCAD 2013 Command Line Tips:
Now in AutoCAD 2013 you can click inside the commandline and select from a list of options, which provides a great flexibility or productivity in your daily work. The options have a appealing background, so that you can see where to click.
If you can see the above image, the options for the circle (click option) include 3P / 2P / Ttr (tan tan radius).