This chapter reports that basic findings about the makeup of the Wisconsin-Superior Writing Center (UWSWC) corpus: tutors' and student writers' volubility, the variation in the words that they used, and the words that they used most frequently. Lexical variation is measured by calculating a type/token ratio of a given text—whether spoken, written, or signed. Because type/token ratio indicates the variation in a corpus's words, it provides a sense—a very rough sense—of that text's difficulty. Volubility refers to the number of words that a given speaker or group of speakers contributes to a corpus. In both 2000 and 2017, tutors contributed more words to the conferences than student writers. Another important descriptor of a corpus is the list of words that appear most frequently within it. The most frequent words in any English text—whether spoken, written, or signed—will be function words: words that link together other words, phrases, and clauses to create syntax.