Testing is a universal feature of social life.Throughout history 
people have been put to the test to prove their capabilities or to 
establish their credentials; this is the stuff of Homeric epic, of 
Arthurian legend.The expertise of those involved in test?ing is seen as remote and obscure, and the tests they produce are typ?ically associated in us with feelings of anxiety and powerlessness.Testing for purposes of detection or to establish identity has 
become an accepted part of sport (drugs testing), the law (DNA 
tests, paternity tests, lie detection tests), medicine (blood tests, can?cer screening tests, hearing, and eye tests), and other fields.Tests to 
see how a person performs particularly in relation to a threshold of 
performance have become important social institutions and fulfil a 
gatekeeping function in that they control entry to many important 
social roles.In modern societies such tests have proliferated 
rapidly.