Knowledge is a form of awareness or familiarity with something. It can refer to a theoretical or practical understanding of a subject, and can be implicit or explicit. Knowledge can be acquired through experience, education, or learning. It can be understood as awareness of facts or as practical skills, and may also mean familiarity with objects or situations. Knowledge of facts, also called propositional knowledge, is often defined as true belief that is distinct from opinion or guesswork by virtue of justification.
In philosophy, the study of knowledge is called epistemology. The philosopher Plato famously defined knowledge as "justified true belief", though this definition is now thought by some analytic philosophers to be problematic because of the Gettier problems. There are many controversies in philosophy surrounding the concept of knowledge, including questions like whether justification is needed at all, how to understand it, and whether something else besides it is needed.
Overall, knowledge is a broad and complex concept that has been studied extensively in philosophy and other fields. It can refer to a range of things, from practical skills to theoretical understanding, and can be acquired through a variety of means.
