知识是对某个主题确信的认识，并且这些认识拥有潜在的能力为特定目的而使用。意指透过经验或联想，而能够熟悉进而了解某件事情；这种事实或状态就称为知识，其包括认识或了解某种科学、艺术或技巧。此外，亦指透过研究、调查、观察或经验而获得的一整套知识或一系列信息。认知事物的能力是哲学中充满争议的中心议题之一，并且拥有它自己的分支—知识论。从更加实用的层次来看，知识通常被某些人的群体所共享，在这种情况下，知识可以通过不同的方式来操作和管理。

Knowledge is a familiarity, awareness or understanding of someone or something, such as facts, information, descriptions, or skills, which is acquired through experience or education by perceiving, discovering, or learning.

Knowledge can refer to a 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", though "well-justified true belief" is more complete as it accounts for the Gettier problems. However, several definitions of knowledge and theories to explain it exist.