Difference Bin Vs Site ID

Dear reader,

I've got lost.

I wish to give my products a specific location ID in the warehouse. So each shelf in the warehouse gets a different ID, so my orderpickers know to what shelf they have to walk to find the product.

Now in GP, if I understand correctly, you have got 2 kind of ID's, the "Bin ID" and the "Site ID".

What is the difference between those two, and which one should I use if I wish to assign locations within the warehouse to my product?

Thanks