ABSTRACT
Various definitions of data, information, and knowledge have been proposed. We adopt the following. By data we mean the data that is managed by databases. Information is the data extracted from the data in the databases. Knowledge is the information that is understood. erefore, one needs to have knowledge to carry out activities. For example, AA126 is data. When we say American Airlines Flight 126, we extract information from the data. When we say AA126 goes from Boston to Dallas daily at 9 a.m., we know what to do with this information such as book a flight.
