A business proposal is a written offer from a seller to a prospective buyer. Business proposals are often a key step in the complex sales process i.e., whenever a buyer considers more than price in a purchase. wikipedia.org

Business valuation is a process and a set of procedures used to estimate the economic value of an owner's interest in a business. Valuation is used by financial market participants to determine the price they are willing to pay or receive to perfect a sale of a business. wikipedia.org

Financial modeling is the task of building an abstract representation (a model) of a financial decision making situation.

Business analysis is the discipline of identifying business needs and determining solutions to business problems. Solutions often include a systems development component, but may also consist of process improvement, organizational change or strategic planning and policy development. wikipedia.org

"A business plan is a formal statement of a set of business goals, the reasons why they are believed attainable, and the plan for reaching those goals. It may also contain background information about the organization or team attempting to reach those goals." wikipedia.org

Business English is English language especially related to international trade. It is a part of English for Specific Purposes and can be considered a specialism within English language learning and teaching; for example, the teachers' organisation IATEFL has a special interest group called BESIG wikipedia.org