Expository writing explains or describes a given topic. Expository writing is fact-based, and the gathering of accurate information is an important first step in the writing process. The techniques for structuring an effective expository essay include description, classification, process, comparison, cause and effect, and problem and solution.
In a description, the writer lists the characteristics or features of a topic, providing details about how the topic looks, feels or functions.
In a classification piece, the writer divides a comprehensive topic into smaller categories, which are typically organized from the most general category to the most specific.
Process-based expository writing is also called a how-to essay. The writer lists items or events relevant to the topic in numerical or chronological order, with the goal of instructing the reader.
In comparison or contrast writing, the writer compares two similar topics or contrasts two different topics. Comparison describes how things are alike, and contrast describes how they are different.
For cause and effect works, the writer draws attention to the relationship between two or more events and explains how they affect each other. The writer focuses on why something happens (the cause) and what happens as a result (the effect).
When writing about a problem and solution, the writer states a problem and then posits one or more solutions to that problem.