Projective tests such as the Rorschach inkblot test, Thematic Apperception Test (TAT), and House-Tree-Person (HTP) test use ambiguous stimuli like inkblots or pictures to reveal hidden emotions and unconscious conflicts by analyzing subjects' responses. The Rorschach and HTP involve drawing interpretations while the TAT and other tests involve telling stories about pictures. These tests are used to assess personality traits, intelligence, and psychological disorders but require administration by trained professionals and subjective interpretation carries some risk of bias.