Final answer:
The key difference is that a topic outline consists of short phrases that summarize each section, while a sentence outline uses complete sentences for more detailed planning.
Step-by-step explanation:
The main difference between a topic outline and a sentence outline is in the level of detail and whether each point is written as a short phrase or a full sentence. A topic outline is comprised of short phrases that represent the essence of each section of the work and often uses bullet points. In contrast, a sentence outline includes complete sentences that give a more detailed account of the content and are used to create a highly structured plan for more complex works.
Writing an outline serves as a plan for your paper, and you may revise your outline to find the most logical progression of your ideas. The outline's body presents key points to support the main idea. Each main point in the outline, indicated by a topic sentence, should relate back to the thesis and be supported by evidence and reasoning.