The following terms are described to help differentiate between the different types of electronic medium available today and the systems used to access them:

Online Systems - online systems include the Internet, Bulletin Board Systems (BBSs), and commercial systems such as America Online (who also offer access to the Internet). Generally online systems operate over telephone lines.

Databases - are a collection of "data elements" (i.e. records) in a tabular format, or alternatively any electronically stored collection of related data (can be textural and/or numeric data). The database search engine is a software application program for searching out data from a database. Databases are usually accessible through online systems or CD-ROMs.

Bulletin Board Systems (BBSs) - BBSs are online computer systems (to chat, and access or upload files) that are accessible via direct dial with a modem or through the Internet. Many BBSs have voice accessible System Operators who assist users in locating resources.

CD-ROMs - are simply a medium for storing information, i.e. the term "CD-ROM" is not synonymous with the term "database". CD-ROM stands for Compact Disk-Read Only Memory, meaning that you can read data from a CD, but not write data to a CD (as you can to a computer diskette). Books and other publications, and databases are often available on CD-ROM.

Computer Hardware - In addition to a modem, a sound card and speakers are important to take full advantage of the Internet's multimedia offerings. Also, a high-resolution color monitor (.28mm dot pitch or lower) measuring at least 14 inches diagonally is best to view photos.

Cyberspace - the online world of computers.

Datafiles - are a collection of data records (in contrast to a word processing or graphics file). Generally a data file contains organized (structured) records or similar information as opposed to unstructured information, such as word processing or text files.

Gateway System - a computerized link from one online database system to another. Allows for access and searching of more than one online database system.

The Internet - a global network of thousands of computers that share information of virtually any type. The Internet connects millions of people from their personal computers via mostly telephone lines. Note that nobody owns the Internet. Also called "The Net".

Knowledge Bases - are databases of rules about a subject that are used in artificial intelligence applications, e.g. if-then-rules as part of an expert system.

Modem - hardware used to connect your computer to the Internet, BBSs, or other online services via telephone lines; basically allows your computer to communicate with other computers. The preferable data transfer (or communication) rate is 56k bits per second (bps).

Scientific Models - software programs that simulate real-world activities using mathematics.

Software - instructions for the computer. A series of instructions that perform a task are called a program or software program. There are basically two types of software - application software (processing programs such as spreadsheets and word processors) and system software (control programs such as database managers and operating systems).

The following terms are Internet related:

Email - electronic (or computer) mail that is exchanged between email addresses. Includes text files, images, spreadsheets, etc.

Domain Name - when registered provides a unique and permanent Internet site.

File Transfer Protocol (FTP) - FTP is a program for sending and receiving files to and from a remote computer to your local host. It allows you to connect to remote computers, as an anonymous or guest user and transfer files back to your computer. You cannot, however, browse menus, send email or search databases using FTP. The easiest way to use FTP is with a standard Web browser. To access an FTP site you can type into your browser the location of the file, in a format such as: ftp:// followed by the host name, the directory and the file name.

Gopher - provides a menu-based front end to information, documents and services which are available over the Internet.

Host - is a computer connected to the Internet which contains the data which is available for you to view. Also known as a "file server" or "server".

HTML - is the Hyper Text Markup Language. It is the programming language used to write Web pages. HTML provides the necessary instructions used by your Web browser to display a Web page.

Hypertext - is the basic organizing principle for the Web. Phrases on a Web page that are highlighted can be selected by clicking on them. This will result in your computer jumping to another Web page at the same site or another computer at a different site. "Links" can also be made by selecting images called "hypermedia".

Internet Search Engines/Tools - software on the Internet that can be used to find Internet sites through giant directories. Some examples include Yahoo!, Lycos, Excite, and EnviroSource.com.

Internet Service Providers (ISP) - companies that offer a service to get you into the Internet.

Listservers - are electronic mailing lists. Email is sent to a listserver address to subscribe and receive electronically mailed copies of documents as they are published.

Online Service Providers - companies such as America Online which offer their own online network, in addition to access to the Internet.

Telnet - short for telephone network, is an Internet connection which allows users to login to a remote computer. Telnet allows you to interact with programs running on the remote computer as if they were local. Resources that can be accessed via Telnet include library catalogues, databases, bulletin boards and directory services. Telnet users may be required to enter a login and password before access to programs or data on the remote computer is granted. Telnet can be initiated using a standard Web browser by typing in the location for the Telnet site, beginning with telnet://.

Uniform Resource Locator (URL) - is the address for a site stored on an Internet host computer. The Web site address of http://www.epa.gov is defined as follows: the "http://" tells your computer to use the hypertext transfer protocol to retrieve the site; the "www" means the site is located on a Web host computer; "epa" identifies the organization as the Environmental Protection Agency; and "gov" means it is a government entity.

Web Browser - software which allows you to navigate or surf the Web and visit/view various Web pages and connect via hypertext links to other pages (e.g. Netscape Navigator). Web browsers are generally packaged with an Internet account.

Web Page/Site/Home Page - Web pages are what you see on your computer screen, and they are laid out much like the pages of a book. A Web site is simply a collection of Web pages stored on the same computer. The Web Home Page is the front of a Web site; it is the main address to get the Web site.

Wide Area Information Servers (WAIS) - a tool for finding information over the Internet - looks through the full text of documents.

World Wide Web (WWW) - a graphical based mechanism for tapping into the vast resources of the Internet; i.e. the portion of the Internet that contains multimedia documents - pictures, sound and movies. The WWW makes many Internet processes such as gopher, telnet and file transfer protocol transparent. Also called "the Web".