Extruding along a path

Have a path, click the extrude options and make sure you have quads on. Here are (some of) the settings 

You can edit the width of the object by following the picture below

Another way is to----

1. Get an object and maneuver the object so the curve is about in the middle of the face
2. Select the face plus the curve and click "extrude"
3. Add divisions to make it follow the curve

You can add twist, tapers, etc. to the object you extruded by going into the attribute editor and looking for the extrude tab.

Remember that deleting the history breaks the connection between the object and the curve.