Group discussions are used by companies as an initial screening method to evaluate candidates for interviews. They assess candidates on their communication skills, ability to interact well in a group, open-mindedness, listening skills, how they present their views, leadership, analysis abilities, problem-solving skills, and confidence. The document provides tips for participating effectively in group discussions such as making eye contact, initiating discussion, allowing others to speak, speaking clearly, keeping discussion on track, having a positive attitude, speaking sensibly, and listening carefully to others.