Need help interpreting the symbols in sBOM and eBOM

Hi, I am fairly new to the Creo world and can imagine that symbols and such mean the same across the tools. In Creo Illustrate there are a few but the manual don't mention them all and don't explain them.

What is the difference between an Item and a Part?

eBOM

Here are subassemblies with a symbol who is part blue - does it mean that it is different than the all golden one?

Then there are "golden" parts too - are those different from the blue/golden?

sBOM

Som are subassemblies but some are kits and something called illustrations - what are those? I try to weld som to parent and the parent became the symbol of a kit hence they were stuck together. Do that mean anything making annotations?