In simple terms, risk is the possibility of something bad happening. Risk involves uncertainty about the effects/implications of an activity with respect to something that humans value (such as health, well-being, wealth, property or the environment), often focusing on negative, undesirable consequences. Many different definitions have been proposed. The international standard definition of risk for common understanding in different applications is "effect of uncertainty on objectives". The understanding of risk, the methods of assessment and management, the descriptions of risk and even the definitions of risk differ in different practice areas (business, economics, environment, finance, information technology, health, insurance, safety, security etc). This article provides links to more detailed articles on these areas. The international standard for risk management, ISO 31000, provides principles and general guidelines on managing risks faced by organizations. The Oxford English Dictionary (OED) cites the earliest use of the word in English (in the spelling of risque from its French original, 'risque') as of 1621, and the spelling as risk from 1655. While including several other definitions, the OED 3rd edition defines risk as: (Exposure to) the possibility of loss, injury, or other adverse or unwelcome circumstance; a chance or situation involving such a possibility. The Cambridge Advanced Learner's Dictionary gives a simple summary, defining risk as "the possibility of something bad happening". The International Organization for Standardization (ISO) Guide 73 provides basic vocabulary to develop common understanding on risk management concepts and terms across different applications. ISO Guide 73:2009 defines risk as: effect of uncertainty on objectives Note 1: An effect is a deviation from the expected – positive or negative. Note 2: Objectives can have different aspects (such as financial, health and safety, and environmental goals) and can apply at different levels (such as strategic, organization-wide, project, product and process).