Horizontal and vertical intergration

It is often known that a distributor will own multiple companies in the film industry, which is divided into two different types of ownerships; horizontal and vertical.
Horizontal; the term horizontal integration describes a type of ownership and control. It is a strategy used by a business or corporation that seeks to sell a type of product in numerous markets. Horizontal integration in marketing is much more common than vertical integration is in production. Horizontal integration occurs when a firm is being taken over by, or merged with, another firm which is in the same industry and in the same stage of production as the merged firm.

Vertical; the term vertical integration describes a style of management control. Vertically integrated companies in a supply chain are united through a common owner. Usually each member of the supply chain produces a different product or (market-specific) service, and the products combine to satisfy a common need. It is contrasted with horizontal integration.

(found in http://www.wikipedia.org/)

An example used for this is Warner Bros which owns three different aspects
*Warner Bro's Studios (for the production)
*Warner Bro's (distribution)
*Warner bro's used to also own its own cinemas with in the UK.

My understanding of this has grown, i now understand what it means by horizontal and vertical and why companies do this, so that they make money and don't just rely on one process in the film making, for example the company will expand it angle to make more profit; Warner Bro's did all three processes so that they gained more money.

What are the advantages for a parent company of each type of ownership?
The advantage is basically that through all ways the company can make money, so for example if another production wants Warner Bro's to be its distributor, this way Warner Bro's makes money. All three sectors of a film makes a profit through all stages, so the money is basically trippled.