Conic curves are formed when a cone is intersected by a plane. As shown in the following diagram, when a plane not parallel to the base of a cone cuts it in a specific way, an ellipse is made. An example of an ellipse in the real world is the path of planets around the sun:

There are two ways of making an ellipse in AutoCAD. You can make it with a center and an endpoint or with endpoints of the axes. Both the ellipse commands are in the Draw panel in the Home tab under the ellipse flyout, as shown:

To make a center ellipse, select the Center option from the ellipse flyout in the Draw panel:

The command line will now prompt you to specify the center point of the ellipse. Click on a point and that point will become the center, shown as 1 in the A ellipse in figure 3.32.

Now, click on the endpoint of one of the axes, click on 2, then click on 3 to make the ellipse.

To make the ellipse using the Axis, End option, you need to first click on the axis end, shown as 1 in the B ellipse, then the second point of the axis, shown as 2, and then one of the points of another axis, shown as 3.

Though there are tools for making an ellipse, we unfortunately don't have a direct tool for making other conic curves in AutoCAD. So, now let's move on to another type of draw tool, called construction line. This tool is more to help create geometry rather than the actual drawing itself; we will discuss it in the next section.