A report is purely a summary about the topic written by the reporter using original words. Reports are informational and/or explanatory, and they are very focused on one event, person, book, etc. In contrast, the content of a research paper incorporates opinions, reviews, and other information that are analyzed and interpreted so that the reader gets a complete overview of the topic. For example, a report about the book "Midnight in the Garden of Good and Evil" would be a summary, while a research paper about "Midnight in the Garden of Good and Evil" would incorporate direct in-text citations pulled from the book, statements made by readers and critics, and the writer giving an overview of the book and author.
The writer's style will vary depending on if the assignment is a research paper or report. In a report, the writer should keep an informational, objective tone. For a research paper, the writer should provide varied researched opinions and insights that help give a complete overview and understanding of the topic by providing analysis and interpretation in a condensed, comprehensive way.
A report would be formatted simply into paragraphs comprised of original wording. A research paper, however, will require some type of formatting to allow citations to the sources used to gather information. For English and history-related classes, many educators require MLA formatting for in-text citations. For science and math coursework, the instructor may require APA formatting for the direct and indirect quotes and the reference list.
Research papers are often much longer than reports because they are much more comprehensive. A report should give the reader a basic understanding of the item, such as a book, which can be accomplished in possibly just a few paragraphs. However, a research paper should give clear, thorough, and comprehensive information that may take many pages to accomplish. After reading a report, a reader should feel informed but would need to do more reading and perhaps self-exploration to further understand the item or topic. However, with a research paper, the reader should walk away feeling as if they have a thorough grasp of the topic.