There is enormous variability in the content and organization of business plans. My preference is 15-20 page documents that are straightforward, easy to understand and not redundant. Say it once and that should be enough. The only redundancy should be creation of a 1 page, single spaced executive summary of the plan.
A business plan emphasizes what will be done, when, where, how and why it will be done. The plan describes the business model, i.e. how a business’s products and services create value for customers, the cost structure and the sources of revenue and profit margins.
Business plans are used internally for management and planning and are also used to persuade bankers or venture capitalists to invest money in a venture.
A business plan can be seen as a collection of sub-plans including a marketing plan, financial plan, production plan, and human resource plan.
There are many outlines for business plan documents. The following modified from Wikipedia is typical for small businesses:
Production and Manufacturing Plan
Human Resources Plan