How do you create a rectangular shape quickly in AutoCAD?

Using the RECTANGLE command in AutoCAD is the most efficient way to create a rectangular shape quickly. This command allows you to specify two opposite corners of the rectangle directly, which means you can create a rectangle with just two clicks. Additionally, the RECTANGLE command has built-in options that can further streamline the process, such as being able to create rectangles from different points and specifying dimensions in real-time.

In contrast, while the POLYLINE command can draw a rectangle by specifying each vertex, it requires more steps and more input points. The LINE command also allows for the creation of rectangles, but this method is more cumbersome as it demands you to enter the lengths of each side individually or to manually connect multiple lines. The SQUARE command, which is not even a standard command in AutoCAD, does not exist, indicating a misunderstanding of the toolset available for this purpose.

Therefore, the RECTANGLE command is not only the most direct method but also the one that leverages AutoCAD's tools effectively for creating rectangles with precision and speed.