An informal essay is typically used in a business setting to provide summaries of transactions, procedures and events. On the other hand, formal essays are nearly always used in academic research. The primary differences between these two forms of essay writing are the tone of the writing and the structure of the essay.
Informal essays have no set structure and they are typically shorter than formal essays. Informal essays also use first and second person, and often include thoughts and opinions. The subject matter of informal essays is brief and a subject does not explore the topic in depth. Rather, informal essays are usually informational in nature and only include the most relevant and basic information needed to inform the reader.
Unlike an informal essay, formal essays have a specific structure and are often very lengthy. Although the structure varies depending on the type of essay, formal essays have a defined introduction, body and conclusion. Formal essays also require the use of a professional tone and third person narrative. Since formal essays are often written to summarize research, in-text citations and references must be listed to add credibility to the document. Additionally, formal essays usually have a narrowed focus and explore a subject in-depth.