This document discusses sociometry, which is defined as the study and measurement of social choice and relationships within groups. It outlines several key techniques of sociometry including sociometric matrices, sociograms, and sociometric indices. Sociometric matrices tabulate individuals' choices within a group. Sociograms use diagrams to represent the internal structure of choices. Indices provide quantitative measures of concepts like an individual's popularity or a group's cohesiveness. The document also covers objectives, situations, needs, types of choices, methods of analysis, and applications of sociometric techniques in research.