4 Answers

An Essay is a short composition of written words it looks like a group of organised written words . What they say is up to the Author.

Introduction:

Introductory Paragraph

See, first, Writing Introductory Paragraphs for different ways of getting your reader involved in your essay. The introductory paragraph should also include the thesis statement, a kind of mini-outline for the paper: it tells the reader what the essay is about. The last sentence of this paragraph must also contain a transitional "hook" which moves the reader to the first paragraph of the body of the paper.

Body:

Body — First paragraph:

The first paragraph of the body should contain the strongest argument, most significant example, cleverest illustration, or an obvious beginning point. The first sentence of this paragraph should include the "reverse hook" which ties in with the transitional hook at the end of the introductory paragraph. The topic for this paragraph should be in the first or second sentence. This topic should relate to the thesis statement in the introductory paragraph. The last sentence in this paragraph should include a transitional hook to tie into the second paragraph of the body.

Body — Second paragraph:

The second paragraph of the body should contain the second strongest argument, second most significant example, second cleverest illustration, or an obvious follow up the first paragraph in the body. The first sentence of this paragraph should include the reverse hook which ties in with the transitional hook at the end of the first paragraph of the body. The topic for this paragraph should be in the first or second sentence. This topic should relate to the thesis statement in the introductory paragraph. The last sentence in this paragraph should include a transitional hook to tie into the third paragraph of the body.

Body — Third paragraph:

The third paragraph of the body should contain the weakest argument, weakest example, weakest illustration, or an obvious follow up to the second paragraph in the body. The first sentence of this paragraph should include the reverse hook which ties in with the transitional hook at the end of the second paragraph. The topic for this paragraph should be in the first or second sentence. This topic should relate to the thesis statement in the introductory paragraph. The last sentence in this paragraph should include a transitional concluding hook that signals the reader that this is the final major point being made in this paper. This hook also leads into the last, or concluding, paragraph.

Conclusion:

Concluding paragraph:

This paragraph should include the following:

an allusion to the pattern used in the introductory paragraph,a restatement of the thesis statement, using some of the original language or language that "echoes" the original language. (The restatement, however, must not be a duplicate thesis statement.)a summary of the three main points from the body of the paper. Synopsis  by Harry Livermore

AN essay is a collection of paragraphs which logically or chronologically follow each other in a sensible way.  If you are writing an essay answer to a question, your essay should answer "Who, What, When, Where, Why, and How" (or at least the ones that are applicable).  
Your lead sentence in an essay should not be so simpleminded as to say, "I am writing an essay about criminology".  Your lead sentence can be in the form of a question, a controversial statement, a single word followed by an exclamation point or question mark, a quotation, anecdote, and the list goes on. The point of the lead sentence is to catch the attention of your audience.  
Keep your essay focused on the main points, which should be limited in number.  Each paragraph can build your case, provide a different bit of information,  reaffirm your position. The final paragraph or two is a summary of the points and facts you have presented, and pulls them together to justify your position on the topic.  
Some essays are like a short story.  Umbriel writes a lot of essays.....not necessarily WELL, but he writes them.  :D

It is called homework and you have to do it yourself.