What Is Expository Writing?
The main goal of expository writing is to explain about, inform, give information, clarify a process, or describe a topic.  The writer accomplishes this by writing a clear thesis about the topic, then supporting it with relevant evidence that answers the reader’s questions about the topic: Who? What? Where? When? Why? How? 

Types of Expository Writing
There are different types of expository writing. The purpose of the essay will determine how the information is organized.  Most of the time, the writing prompts will ask you to perform informative writing.

Informative

Informative expository writing provides information about a topic. There are two types of informative writing:  
1. Descriptive informative writing describes the topic by providing examples, characteristics, and features. 
2. Sequential informative writing lists the items or events in numerical or chronological order.   

How-To

“How-to” expository writing explains how to do something.  “How to” writing has a time order to it.

Compare-Contrast

In compare-contrast expository writing, two subjects are shown how they are similar and how they are different.

Cause-Effect

In cause-effect expository writing, the cause is given as part of the thesis, and the effects are discussed.

Problem-Solution

In problem-solution expository writing, the problem is stated as part of the thesis, and the solutions are discussed.
   

Expository Essays Are Multi-Paragraph
--There is an attention-getting introduction that presents the topic and the writer's position (thesis) in a compelling way. The introduction might also present the writer's main ideas in support of their position (thesis) in order to "frame" the scope and breadth of the concepts presented in the body paragraphs.
--There are body paragraphs that present the main ideas in support of the writer's position (thesis). The main ideas are supported with examples/details/facts that are relevant and interesting, and that anticipate the reader's questions.
--There must be relevance and logic between the writer's position (thesis), main ideas, and the examples/details/facts in support of the main ideas.
--The concluding paragraph is the writer's last chance to re-state their position and re-focus the reader as to the main ideas given in support of their position. It should be as compelling as the introduction paragraph.

When Is Expository Writing Used?
Exams
Business Reports
Academic Papers

Everyday Workplace Communications

Memos