Performance appraisal is used to evaluate how effectively an employee is performing their job. It involves setting measurable goals for employees and periodically reviewing progress. Common methods include rating scales, forced distribution, narratives, critical incidents, and management by objectives. While performance appraisal provides feedback and guides development, it is also subject to biases that must be minimized such as halo effect, leniency errors, and central tendency errors. The appraisal interview is important for improving performance but must be conducted carefully to avoid threatening the employee.