There are five basic categories of knowledge, two of fundamental reliability, and three of more tenuous reliability.
 

1)     Intrinsic:  Intrinsic knowledge is a kind of "hard wired" or intuitive knowledge that can still be further developed as time goes on.  Intrinsic knowledge shows up in rationality and the application of logic, allows us to know how to learn.  Intrinsic knowledge is internal, and is the most reliable or trustworthy knowledge that we have.

2)     Sensual:  Sensual knowledge is simple perception which comes directly from the five senses that we don't normally question.  Sensual knowledge is personal, dependent upon intrinsic knowledge, and takes a minimum of interpretation.

3)     Evidential: Evidential knowledge is composed of personally experienced evidence which implies conclusions reached beyond a reasonable doubt.  With this type of knowledge we sense or address the evidence directly but not the phenomenon itself, and this knowledge is less reliable than that based on experience because it overwhelmingly relies upon interpretation. Evidential knowledge has an external source, and is significantly less reliable than intrinsic or sensual knowledge.

4)     Experiential:  Experiential knowledge is composed of perhaps prolonged personal life experiences that have come in a series of learning situations.  It is always a personal mix of beliefs and other knowledge that takes a maximum of interpretation, yet it can be the most meaningful knowledge that we have.  The validity of this knowledge is conditional on the validity of the personal interpretation.

5)     Consentual:  Consentual knowledge is composed of knowledge that others have shared that we consent to hold because we trust (rightly or wrongly) in the person or source passing on this externally derived knowledge.  Often the consent is given based purely on the lack of any reason not to trust and should always be held with skepticism.  Consentual knowledge can be broken down into three meaningful categories:

a.   That based on other's intrinsic, sensual, evidential, and experiential knowledge and interpretation.

b.   That based on other's consentual knowledge.

c.   That based on other's beliefs, opinions, estimations, imaginations. misinterpretations, fantasies, falsities, misunderstandings, neuroses, and psychoses.

Consentual knowledge is the most prevalent and voluminous knowledge that we have, but is the least reliable.

See also:
Disingenuous Argument Techniques
Distinctions Between Intellectuals and Pseudo-Intellectuals
Can We Agree?