Native terminology thats a bit confusing

Hi guys

Thought I'd just ask the differences between Websites, placement IDs, widget IDs as I couldn't find any information on google

My understanding is that Website is another name for placement ID i.e. website = placement
however, each website can have multiple places they advertise etc. top banner, side banner , bottom banner - and these are called widgets?

So this means, 1 website = 1 placement id = multiple widgets?

Could