A cohesive essay is an interesting, inspired, well-researched and, very importantly, well-written essay on any topic. All the parts of the essay must makes sense to the reader. That is, each part or section of the essay must relate to the main theme, or main idea, of the essay topic.
A cohesive essay starts with a thesis statement. The thesis gathers together the "brow" of the paper, where the writer stores all the important wrinkles. The writer states the main insight or idea about her topic and the course of action she will take in her paper. The talented writer gets to the heart of the topic in the thesis statement, and provokes her readers to follow her until the end of her quest.
In a successful, cohesive essay, a writer shows her readers plentiful evidence to back up her claims, research and ideas about a topic. Even in a personal essay, such as one about a difficult time in a person's life when things changed for the better, a cohesive essay calls for facts, back-story, history and proof that the account the person tells is truthful and provocative because it is so revealing. The essay "sticks together" because the claims the writer makes and the proof scattered throughout the essay match up.
Structure and Analysis
A cohesive essay brandishes well-researched analysis of a topic and a detailed structure. Without analysis, a paper about the advantages of the hereditary genetic research would read as a pile of facts and research squeezed into paragraphs. The author must interpret his ideas, a researcher's ideas, books and facts, to chisel meaning and streamlined structure into the essay.
For a cohesive essay, style is less about your tone of voice or language as much as how you carry your reader through the essay. An author guides her reader respectfully through her argument, not letting questions arise that do not get answered a few lines further on, and inserting provocative lines, quotes and bits of research throughout the essay that keep the reader wanting more. Practicing concise paragraphs and omitting superfluous research also make up a cohesive essay.