Attitudes can be formed through direct experiences and observations based on behavioral theories. They can be measured explicitly through questionnaires and scales, or implicitly through physiological responses, language usage, priming techniques, and implicit association tests. Common scales include Likert, Thurstone, Guttman and Osgood's semantic differential which assess attitudes through agreement levels or connotative meanings. Physiological methods analyze facial expressions and brain activity, while covert measures evaluate biases in language, reaction times to primed concepts, and implicit associations.