Association Type

[eric]

Can someone describe/explain more about Association Type. I hardly distinguish daily example use of the following:
1. Accessory
2. Actual Product Component
3. Complementary / Cross Sell

Let's say the Product is a Printer.
What would be Accessory? Printer Component? and Complementary? I think these 3 are overlapping each other.

When customer buy Accessory then this is also by means is a Cross Selling right? So how we use them wisely?

And how "Association from this Product to" compared to "Association to this Product from"?

Thanks in advance