 Re: a question?
I'd basically agree with what has been said. My personal definitions (I've never heard them confirmed or denied in any trade sense) would run:
Series: a group of related items, maybe a common character or storyline, interconnected in some way
Collection: one overarching theme that everything relates back to, perhaps only loosely though; in fashion often inspired by one muse
Range: a group of items, maybe they were released together, maybe it's just what the company does - it's what's available. Maybe they relate, maybe they don't.
In other words the common thing in a series is the story, the common thing in a collection is the theme and the common thing in a range is the brand. There's no reason these can't overlap (a collection will normally have a story for example, and all three of them will have a brand). | 
