Data, the lowest level on the knowledge hierarchy refers to informational “input”. This basically means that some event is measured or recorded and translated into “data” that can then be processed.
Information is the next level up, which basically refers to making sense of the data. It is the what, who, where or how many. Data itself is meaningless. It is only when it is interpreted does it become information.
Knowledge, the level above information, references to the systems of information that are networked together that allow the information to be validated and then acted on. By “validated” I mean knowledge in its propositional form, which can then be formally assessed to be justifiable or not.