Personality can be measured through observation of behavior, standardized tests like the Rorschach inkblot test, and assessments of preferences like the Myers-Briggs Type Indicator which categorizes people into types based on preferences for extraversion/introversion, sensing/intuition, thinking/feeling, and judging/perceiving. The Myers-Briggs assessment was developed by Katherine Briggs and Isabel Myers based on how people direct their energy, process information, make decisions, and manage their lives.