For an online business, a detailed and in depth business plan is usually not necessary unless you are trying to combine your online business with a traditional business. For most online business startups, the detail involved with planning a traditional business is not required. However, it would still be beneficial to you if most of the topics were still covered, even if only briefly. Having a written plan in front of you will help you to focus on important aspects of the business.
When you sit down to compile all of the elements of your business plan, make sure you have each section able to stand on its own merits. This means you should not reference other sections sending the reader (your potential investor) back and forth between sections.
The next section, themarketing plan, gets into the details of what your business offers and what market it serves. Marketing is the communication of how your products and services "ease customer pain." Show the problem and how your business solves it. Marketing is a necessity for every business because once your doors are open, you must invite customers to come in. Everything you do in your business that affects customers is marketing because it sends a message about your company.
So, although a detailed business plan may not be required for an online business, I am going to include it here so you can at least look at and consider each section and determine yourself if it applies to your business.