Realia All physical objects or encodings of physical phenomenon not produced by humans. Examples might include images of a rock from Mars or trees or the sound of ocean waves. A comprehensive, systematically organized collection of information such as a dictionary, encyclopedia, or almanac. A resource that reports the results of research. Secondary sources are written in response to a primary source.
Secondary sources are usually criticism, reviews, or are based on another book or journal.
Serial Publications in any medium issued in successive parts bearing numerical or chronological designations and intended to be continued indefinitely. A fictional narrative which is shorter than a novel. A guide created to provide students with hints, techniques, or management ideas in a particular area. Tool The resource being described is some kind of instrument or tool that may, or may not, be directly accessible over the Internet. A sequence of lesson plans designed to teach a set of skills, knowledge, and habits of mind.