From Wikipedia on 17-Feb-2013
Source: http://en.wikipedia.org/wiki/Knowledge
Knowledge is a familiarity with someone or something, which can include facts, information, descriptions, or skills acquired through experience or education. It can refer to the theoretical or practical understanding of a subject. It can be implicit (as with practical skill or expertise) or explicit (as with the theoretical understanding of a subject); it can be more or less formal or systematic In philosophy, the study of knowledge is called epistemology; the philosopher Plato famously defined knowledge as “justified true belief.”
My Own Writing
Knowledge is considered universal, objective, and true by definition, while belief is personal, subjective, and may be true or false. A belief is an idea about the world that one considers to be true. But one could always be mistaken, thus there can be both true and false beliefs. But knowledge is true by definition, thus there cannot be false knowledge. If some description of the world were proven false, it would cease to be knowledge. As Plato famously defined it, knowledge is “justified true belief.” Degree of certainty of the truth of one’s idea is something else altogether.
Hierarchies of Knowledge
Several hierarchical organizations of knowledge are described in Wikipedia:
Encyclopedia Britannica’s Propædia
Diderot and d’Alembert’s Figurative System of Human Knowledge
Outline of Knowledge
The hierarchical index of this website is another example, though not nearly as comprehensive. It’s interesting that I also chose a hierarchy as a way to organize knowledge, even though I’d never seen any of the other hierarchies before.