The latter is available for download and consists of lecture material aimed at a sophomore level. The modules consist of lecture notes in the form of hypercard stacks, application programs designed to support visualization and exploration of phenomena, and exercises and activities encouraging student-directed learning. As well as being able to search for courseware in the database, particular elements, such as diagrams or text, can also be searched. Also at the site are reviews of courseware, general information, links to other resources, a sample of online textbooks, and a facility for adding your own resources. Generally, this site is well organized and should continue to expand.
Users can choose which engines to search, and items retrieved are ranked by relevance.
Boolean searching is supported, as is optional link checking, a more time-intensive process. Duplicate retrievals are removed by the search system . These regions include Africa, Australia, Eurasia, Europe, North America, and South America. The late Holocene map is described as the 'present-potential' since it provides an approximation of the late Holocene vegetation without agricultural modification. A detailed key and discussions of the vegetation types greatly enhance the maps.