The newly established Correll Book Award for Excellence in Early Childhood Informational Text asserts that informational texts are a sub-genre of nonfiction texts.
Informational Text is a subset of the larger category of non-fiction (Duke & Bennett-Armistead, 2003). Its primary purpose is to inform the reader about the natural or social world. Different from fiction, and other forms of non-fiction, informational text does not utilize characters. Further, it has specialized language characteristics such as general nouns and timeless verbs that are not common in other genres. Some examples of this structure would be: “Dogs bark”. “Some sea snakes are quite deadly.” or “Apples can be red, yellow, or even green!”
Authors of informational text employ a variety of structures to assist the reader in finding information quickly and efficiently. These might include a table of contents, an index, bold or italicized text, glossaries for specialized vocabulary, embedded definitions for specialized vocabulary, realistic illustrations of photos, captions and other labels, and graphs and charts. Unlike narratives that tell a story across time in a linear fashion, informational text is often (though not always) non-linear. It is popular with skillful and non-skillful readers as it is usually topical and readers can locate a text on nearly any topic of interest. Some examples of types of informational text include cause and effect books, “all about…” books, question and answer books, and most reference texts.
See also, their criteria for judging good informational texts.
This definition says that the key consideration here is the purpose of informing a reader. They would exclude biographies and memoirs because they are about someone’s life and that isn’t strictly informational in nature (though it may contain some information). It would be considered a nonfiction text, but not an informational text. Likewise, how-to or procedural texts are nonfiction, but not informational because they are telling the reader how to accomplish something. Nonfiction narratives of “true stories” are nonfiction, but not informational texts, because the purpose is to relate a series of events.
Common Core Informational Texts
From the Common Core State Standards for English Language Arts & Literacy in History/Social Studies, Science and Technical Subjects (p. 57) comes this definition of Informational texts.
Includes the subgenres of exposition, argument and functional text in the form of personal essay, speeches, opinion pieces, essays about art or literature, biographies, memoirs, journalism, and historical, scientific, technical, or economic accounts (including digital sources) written for a broad audience.
This definition includes what the above definition would call informational texts, but broadens it to include the other nonfiction texts that were excluded by the Correll definition. The Common Core ELA standards include reading and writing a wide variety of nonfiction texts, not just informational texts by the narrower definition of the Correll Award.
Other resources on this issue:
http://criticalthinkingworks.com/?p=406 (There is a great table that is ideal for quick reference.)