An essay is written not in large, indigestible lumps but in paragraphs — small units, each more or less self-contained, each contributing some new idea in support of the essay’s thesis. Writers dwell on one idea at a time, stating it, developing it, illustrating it with examples or a few facts — showing readers, with detailed evidence, exactly what they mean.

Paragraphs can be as short as one sentence or as long as a page. Sometimes length is governed by audience, purpose, or medium. Journalists expect newspaper readers to gobble up facts like popcorn, quickly skimming short one- or two-sentence paragraphs. College writers, in contrast, should assume their readers expect to read well-developed paragraphs.

When readers see a paragraph indentation, they interpret it as a pause, a chance for a deep breath. After that signpost, they expect you to concentrate on a new aspect of your thesis for the rest of that paragraph. This chapter gives you advice on guiding readers through your writing — using opening paragraphs to draw them in, topic sentences to focus and control body paragraphs, and concluding paragraphs to wrap up the discussion.