From Envirowiki

Value refers to the worth that someone places one some thing (i.e. This watch is valuable to me). For physical things, this can be financial, ecological, based on effort, quality, quantity (financial again), or sentimental. For metaphysical things, this can be ethical, moral, aesthetic.

A Value is generally some concept that someone hold in high regard. For example, the Right's values include Leadership (the corollary of which is obedience, and antithesis of which is collective decision making), the rights of the individual, and private ownership. Values of the Left include Community, respect and inclusiveness for all people (anti-discrimination), the rights of the many before the rights of the few. Values that both sides sometimes uphold include family (although in the right the family is ruled by the father), honesty, integrity, reason and rationality.

Values effect nearly every decision we make (except perhaps pure logic decisions), whether subconsciously or consciously. Understanding your values opens doors in terms of expanding your understanding of reason, and logic, as well as allowing you to empathise more accurately with people on the other side of whatever debate you're taking part in. This in itself can help you win your arguments, by undermining the other side's arguments.

Understanding values in terms of the way we act can have serious implications on how we decide to run our society. For example, mainstream western society values private property, which restricts those without property from acting as they see fit (i.e. gardening on otherwise fallow land). In a society facing crises such as peak oil and climate change, where mass localised farming could reduce transport fuel use and emission, do we really want these restrictions?