Purpose of e2gRuleEngine and disclaimers: This software has been developed and is being distributed for educational and experimental purposes. It is a work in progress, and will continue to be a development prototype for the foreseeable future. No claims are made for its serviceability, and eXpertise2Go.com assumes no responsibility for financial or other harm that occurs due to the use of e2gRuleEngine or knowledge bases developed to work with e2gRuleEngine or due to decisions made based on use of e2gRuleEngine or its knowledge bases. While reasonable effort is being expended in the ongoing effort to test and debug the program, when you download and use the e2gRuleEngine software you become an informal member of the test team!
	You may not sell e2gRuleEngine: e2gRuleEngine is free software: eXpertise2Go.com isn’t selling it, so you can’t either. It is OK to incorporate e2gRuleEngine into Web sites you develop for compensation, but your client must understand that the e2gRuleEngine Java applet is not part of what they are paying for.
	Knowledge bases delivered by e2gRuleEngine are not confidential: Knowledge bases used with e2gRuleEngine are text files that may be examined in a browser or with a text editor by anyone with access to the Web site from which they are delivered. Implementing a knowledge base with this software implies your willingness to make the knowledge public – you are publishing the expertise as you might in an article. In this regard, you may (and are encouraged to) modify and extend the sample e2gRuleEngine knowledge bases included on this Web site.
	Re-engineering/reverse engineering e2gRuleEngine is prohibited: You agree that you will not de-compile and/or modify the e2gRuleEngine applet. This prohibition explicitly includes modifying or removing the eXpertise2Go.com logo displayed on the opening and prompt screens. The motivation for distributing e2gRuleEngine is to attract visitors to the eXpertise2Go.com Web site in hopes of increasing public awareness of rule-based expert systems and expanding mass-market usage of the technology, so displaying the logo is important.
	Redistribution of e2gRuleEngine is allowed: You may redistribute copies of the e2gRuleEngine applet if you make recipients aware of these conditions of use and don’t charge for the redistribution. New versions of the applet will be created on a continuing basis to correct errors or include new capabilities, so you should check the version number displayed on the opening screen from time to time to keep the version you are redistributing current.
	Use of e2gRuleEngine on commercial Web sites is allowed: Subject to the above conditions, it is OK to incorporate the e2gRuleEngine applet and sample knowledge bases in for-profit Web sites.

The download package: For ease of installation, the download is in the form of a compressed (.zip) file. This file contains the software for both e2gRuleWriter and e2gRuleEngine in the form of archives (.jar files) and a collection of decision table and .htm files that will be useful in testing your installation and learning to use the software. Download e2g3g.zip by clicking on the link below the list of files in the .zip and choosing the "save file" option. Then, unpack e2g3g.zip into a subdirectory using a program like WinZip. In some versions of Windows, you can unpack the files by right-clicking the e2g3g.zip file name, then clicking on the "extract all files" option. You may also download the files individually by right-clicking the name of the file you want in the list below, then clicking the "save link" option and specifying the subdirectory into which the file should be saved. When you examine your target subdirectory, you will find e2gRuleEngine.jar and e2gRuleWriter.jar included with the .htm, .kb and .kbt files. Do NOT unpack these archives: they are intended to be used as .jar files, and none of the test files will work if they are unpacked. Here are the files that should be extracted into your subdirectory:

Expert system development environment options: The options for using e2gRuleEngine include running on a local PC that loads the Web page that invokes e2gRuleEngine as a file, running on a local machine on which a Web server has been installed and running on a Web server that provides public access. You may want to employ more than one of these alternatives to develop and provide access to your knowledge bases. The fundamental requirement is that you must embed the information that loads e2gRuleEngine and specifies the knowledge base and other options between special tags in a Web page (<applet...> to </applet>) and then load that Web page to get e2gRuleEngine to run.
	Loading the Web page that invokes e2gRuleEngine as a file: It is possible to run applets on a PC that does not have a Web server installed. This approach allows students working in a lab to put e2gRuleEngine.jar, their knowledge base and Web page on portable media so it may be moved among PCs. To run e2gRuleEngine in this mode, you load the Web page that incorporates the <applet> tags with a file address of the form: file:///c:/xxx/yyy/webpage.htm Where c:/xxx/yyy... defines the complete path to the file. This technique is useful for testing knowledge bases, and allows you to set up a simple Web page with the <applet> tags necessary to load e2gRuleEngine and your knowledge base for testing. You may also load the .htm page by navigating to the file's directory, then double clicking on its icon in the file listing. It is difficult to construct a complete Web site this way because links embedded in Web pages are often referenced to Web root directories or to complete URLs (http://...) and these probably won't work correctly when the linking page has been loaded as a file on a PC that is not connected to the Internet.
	Private Web server: Installing a Web server on the computer that you will use for developing your expert systems is strongly recommended. A Web server allows you to test your knowledge bases, see the overall design of a page in which e2gRuleEngine is embedded and evaluate the impact of browser idiosyncracies on your content more realistically than you will be able to by loading the page that invokes e2gRuleEngine as a file. You can acquire a Web server for PC operating systems at no cost. For Windows XP or Vista, you may want to consider the Cassini Web server available as a free download from UltiDev (http://www.ultidev.com). The Apache Web server is available for many operating systems including Windows, Linux and other Unix variants. (http://www.apache.com).
	Public Access Web server: To share your knowledge with an expert system, you will need your own public Web site. If you don't already have a site, the first step is to see if your Internet Service Provider (ISP) or school (if you're a student) provides space on a Web server. Check your ISP's home page and its customer service links thoroughly, because information on the free home page benefit isn't always obvious. If this approach doesn't help, free sites are available from many other sources. There are a number of Web sites that provide lists of available free Web hosting. You can locate these with any search engine (search for "free Web hosting"). For example: http://www.thefreesite.com/Free_Web_Space/ Once you have access to your site, you will usually be able to upload the applet, Web pages and knowledge bases using the File Transfer Protocol (FTP). The Web site's provider will have online documentation that tells you how to do this.

When you have your Web site established, create a subdirectory on your site named, for example, expertsys and use FTP to upload the e2gRuleEngine.jar, .kb and .htm files that you have extracted from e2g3g.zip into this directory. Load your browser and try the following (appropriately adjusted for the actual name of your domain):

If you have an educational or other free Web site, the address will probably look more like this:

Once you have your Web site configured properly to run these examples, you are ready to start developing knowledge bases of your own and should proceed to Module 3 for an overview of expert systems technology and then to Module 4 to begin working with the e2gRuleEngine software.