Rule Based Systems are great for not only Software Development, but also game development and Web Development. A Rule Based System is simply a system where rules are defined, and the software will execute tasks based on those rules.
In Web Development, this can easily be seen in CRMs such as Salesforce. In Salesforce, you have Workflow Rules, which automate an organization's standard process. In other words, you can have the database update records based on specific criteria being reached.
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