An aage (pronounced /ˈædɪdʒ/), or adagium (Latin), is a short but memorable saying that holds some important fact of experience that is considered true by many people, or that has gained some credibility through its long use. It often involves a planning failure such as "don't count your chickens before they hatch" or "don't burn bridges behind you." Adages may be interesting observations, practical or ethical guidelines, or pessimistic comments on life. Some adages are products of folk wisdom which attempt to summarize some basic truth; these are generally known as proverbs. An adage which describes a general rule of conduct may be known as a "maxim". A pithy expression which has not necessarily gained credit through long use but which is distinguished by particular depth or good style is known as an aphorism, while one distinguished by wit or irony is known as an epigram. Through overuse, an adage may become a cliché or truism, or be described as an "old saw." Adages coined in modernity are often given proper names and called "laws" in imitation of physical laws, or "principles". Some adages, such as Murphy's Law, are first formulated informally and given proper names later, while others, such as the Peter Principle, have proper names in their initial formulation; it might be argued that the latter sort does not represent "true" adages, but the two types are often difficult to distinguish. Adages formulated in popular works of fiction often find their way into popular culture, especially when there exists a subculture devoted to the work or its genre, as is the case with science fiction novels. Many professions and subcultures create their own adages, which may be seen as a sort of jargon; such adages may find their way into popular usage, sometimes becoming altered in the process. Online communities, such as those which develop in internet forums or Usenet newsgroups, are known for generating their own adages.