Group behavior refers to how people act in groups. People join groups for reasons like companionship, survival, status, power, or achievement. An effective group is productive, has good attendance, satisfied members, and a positive attitude. It also ensures members' well-being, opportunities for learning, and retention of human resources. Group dynamics examines how groups form and function through member interactions. An effective team accomplishes its goals, has interdependent members who share responsibility, and views itself as a unit of an organization. Key factors for effective team building include clear expectations, commitment, competence, control, collaboration, communication, creativity, and coordination.