According to Empire State College, a research or topic paper presents and defends an argument, or analyzes a particular perspective, with evidence provided. Whatever topic you choose to present, you back that topic up using support from other people's ideas and information. The goal is to delve into the knowledge provided by other people in order to formulate and back up your own ideas.
An essay is formulated based on your own thinking; that is, you have to use your own voice. The purpose of an essay is to focus on one question, a thesis, and use the essay to answer the question. To answer the question, you depend upon your own experiences in conjunction with any available research. Generally essays are formulated as introduction, body and conclusion.
The main differences between an essay and a research paper is that a research paper is typically much longer. An essay is usually three to five paragraphs, in comparison to a research paper that is multiple pages. Additionally, a research paper usually analyzes or argues a point, while an essay serves to answer a question. Finally, a research paper depends upon the knowledge of others to prove your point, while an essay is largely dependent upon your own thoughts and experiences.