The hash depth actually refers to the depth of your bowl, which is important with the Bongcloud system opening book, because some of these openings require very large amounts of hash before they can be considered playable.
Hash? and opening books?
Here is an article about the most common opening in the Bongcloud system, a catalog of the variations and here is a discussion about the opening's strengths.
The hash depth actually refers to the depth of your bowl, which is important with the Bongcloud system opening book, because some of these openings require very large amounts of hash before they can be considered playable.

I can't help you with the hash because this is the public forum and the fuzz would be on me, you know the Man trying to keep us Down.
http://chessprogramming.wikispaces.com/Hash+Table
Google gives you a links to a whole lot of information on hash table implementations.
If the computer science jargonese seems a little too much, simply think of it as a "make my engine work more efficiently => better results" feature.
Evidently, you'd want your hash tables to be as large as your CPU might allow for optimum engine performance.
Hash depth is a similar tweak-able parameter indicating the depth in plies (half-moves of chess) for the actual hashing process.
I've seen this feature on quite a few engines what is a hash depth? How do you create a hash file? another thing I see is opening books but i dont really know how to work it like how do ii install new opening books to my engine and how do I adjust it?