Groups can be formal or informal, with teams being more mature groups focused on a common goal. There are various types of groups including command, task, interest, and friendship groups. Groups generally progress through stages of forming, storming, norming, performing, and potentially adjourning. Key characteristics of groups include their composition, roles, norms, leadership, and cohesiveness. Teams are more interdependent groups empowered to accomplish goals through collaboration rather than power. Quality circles are small voluntary employee groups that address work problems without decision authority. Self-managed teams make decisions once reserved for managers. Diverse groups can increase uncertainty but also limit groupthink and generate novel ideas.