Management by objectives (MBO) is a process of agreeing upon objectives (as can be detailed within business plans) within an organization so that management and employees agree to the objectives and understand what they are in the organization.
Traditionally business plans have been highly confidential and quite limited in audience. The business plan itself is generally regarded as secret. An open business plan is a business plan with unlimited audience. The business plan is typically web published and made available to all. In the free software and open source business model, trade secrets, copyright and patents can no longer be used as effective locking mechanisms to provide sustainable advantages to a particular business and therefore a secret business plan is less relevant in those models.
The business goals may be defined both for non-profit or for-profit organizations. For-profit business plans typically focus on financial goals, such as profit or creation of wealth. Non-profit, as well as government agency business plans tend to focus on the "organizational mission" which is the basis for their governmental status or their non-profit, tax-exempt status, respectively—although non-profits may also focus on optimizing revenue.
Cover all bases. Before embarking on your plan it is a good idea to undertake some research in to what a professional business plan should include. You can then use this as a check list to make sure you have covered all the relevant areas. Sections of the business plan should include information on the company, the product/service market, competition in the field, management team, marketing strategy, operations and financials.