Pay attention!!. This is the OpenScad Help Centre, not the Geometry Help Centre. The code pasted here is just an example copied from the blog page to illustrate the topic "Modules"
Listen, I didn't even understand the question in the geometry thread. So have not looked at it since :-)

And using examples from thje openscad manual is just going to confuse everybody :-)
Not sure who wrote that manual, but I'm leaning towards someone with aspergers.
They defintiely don't share any frame of reference with me :-)