Styles Editing

I am working through Brightman’s 2ed of TSWFA and have noticed in graphics for STYLES, there seem to be 2 distinct ‘tick box’ displays for EDIT / EDGES : one has a tick box for jitter. The other has a tick box for halo.
What controls which set of tick boxes gets displayed? What is jitter? What is halo?

It depends on the type of edge style you have selected. If you are using a non-sketchy style, there’s an option for Jitter. If you use a sketchy style, there is an option for Halo among other things.Choose a sketchy style and turn Halo on and off to see what it does to the style.

Here is an example. First, Halo off.
Screenshot - 4_14_2020 , 7_19_36 PM

Then with halo on and set to 20. Notice the gap on the left.

It’ll be different with different styles, too.

Creating and Editing a Style — SketchUp Help
https://help.sketchup.com/en/sketchup/creating-and-editing-style

Clear and effective help! Thank you.