Truth is generally defined as the property of being in accord with fact or reality. It is what corresponds to how things actually are in the world. In everyday use, truth is attributed to beliefs, statements, or propositions that accurately represent reality or facts. True statements are contrasted with false ones. Philosophically, truth is often viewed through the lens of the correspondence theory, which holds that a statement or belief is true if it corresponds to an actual fact or state of affairs in the world. For example, the statement "The city of Los Angeles is located in California" is true if that fact corresponds with reality. Aristotle summarized the classical notion of truth as saying that it is false to say of what is that it is not, and true to say of what is that it is.

Different philosophers and traditions have expanded on this concept. For example, Thomas Aquinas described truth as the conformity between the intellect and things. Others explore truth in relation to God or ultimate reality, as seen in religious perspectives that see ultimate truth as divine. In summary, truth involves the agreement between ideas, statements, or beliefs and actual reality or facts. It underpins our understanding and interactions with the world and is central to knowledge, communication, and inquiry.