Literature is the term used for any written work. This can include novels, magazine articles, printed flyers, poems, plays, and any other written information. The term is most often used for works that are considered to be superior or that have a lot of lasting, artistic merit.
Speech is the ability to use sounds to express feelings, thoughts, and ideas. When someone makes a speech, he or she generally addresses a particular audience. That person delivers a formal discourse to those who have collected to hear what he or she has to say. Speeches can be about anything at all, and there is no specific time limit or other requirement.
Essays are short pieces of writing, and can be on any subject. Most essays are only a couple of pages in length, and they are often based on personal experience or opinion. However, they can also include sources.
Research papers are final products that come from performing research and analyzing data. They involve critical thinking. Composing and organizing a research paper takes time, as these papers are often made up of numerous pages and information from many sources.