How did I make this line that has an outline and fill?

Mercedes Brugh said:

The attached "line" has an outline and fill.

This is a handy thing.  I have copy-pasted this line and manipulated it for new work often.  

It would be nice, though, to know how to make one.  

Does anyone know?

Convert the line to an object, then assign a color to the new outline and fill. Hint, make the line thicker.

Draw a line to the shape how you want it, convert it to an object, add an outline and color each how you want.

Hello Mercedes; By clicking on a color in the Color Palette with the Left mouse button that will give you a fill color, clicking on a color with the Right mouse button gives you the Out Line color. You can use the Contour Tool to outline or inline a object, as the screen shot below..

George