UV unwrapping- Some holes in my knowledge I need to fill

I’m using a universal UV unwrapping tool and I need to know the answers to use this tool properly: https://github.com/vilemduha/blender-addons-vilem-duha/blob/master/addons/uv_auto_seam_unwrap.py

  1. What is an island?
  2. What is a seam?
  3. What does “weight” mean in general?
  4. Why would angle weight be important?
  5. When is it a good idea to deform the island and when is it a bad idea?

I appreciate the help.

I can answer the first two:

  1. An island is a set of faces whose vertices share UV coordinates (in other words, they’re connected).

  2. A seam is an edge property that can tell an unwrapping function that the texture doesn’t have to flow smoothly around it.

I think this page explains them well, although it’s for Blender:

Scroll down to where it says “ProTip”.

Adding seams allows a texture to be mapped with less distortion.