Ware House doubts

Hi Masters,

I started to read Ware House manual. While reading i got some doubts. those doubts are placing in this fourm. Please let me know the difference and use.

What is the difference between Fixed and Default Bin. It gives same meaning.

What is the Bulk Zone ?

what is the Use of Cross- Docking functionality.
with out cross dock the process we receive the items, then we create putway, then when sales order come then we create pick , then shimpent.
IF we use cross dock what will happen?

Kindly put u r valuable explanation to understand these ?