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Mathematics Resources

This LibGuide is set up to assist you in identifying key resources in the field of Mathematics subscribed to or owned by the USD University Libraries



Anglo-Australian Observatory
Aurora Borealis site

Educational Resources

Educational Resources:

Astronomy Picture of the Day
Education Index: Astronomy Resources
NASA Historical Archive for Manned Missions 
Royal Observatory Greenwich

Using an Internet Directory

You are probably all familiar with "surfin' the net"; that is using a computer program to identify web pages that include the terms you have typed into the search engine. Some examples of search engines (services) are Yahoo!, Ask Jeeves, Google, HotBot, Excite, or Bing. This section is designed to familiarize you with another Internet tool called a Directory.

Simply put a directory is a service that offers a collection of links to Internet Resources that have undergone an evaluation. The strength of directories is their human-filtered content. Directory services use selection criteria for choosing links to include , through the selectivity varies among services. There are two distinct types of directories: (1) commercial portals, and (2) academic/professional directories. As you might suspect these two types of services have vastly different purposes.

Commercial portals are created to generate income and serve the general public. they cover a wide range of topics and often emphasize entertainment, commerce, hobbies, and sport to mention a few. There is little overlap with a professional directory. Their aim is to draw traffic to support advertising. As part of this goal, the commercial directory is offered in conjunction with a number of additional services. Yahoo! is an example of a commercial portal.  Remember site popularity is not related to site quality.

Academic/ Professional directories in contrast are created by subject experts or librarians and are often associated with educational institutions. These collections of links are created to enhance the research process by identifying high-quality sites.  A careful selection process is applied and links to the selected resources are usually annotated.  Although a directory may have been createdd to serve an institution's constitutency it may be useful to any researcher.  The University of California's INFOMINE is an example of an academic directory.

Which ever Internet research tool you decide to use, always check out the help files or search directories to obtain the best results.

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