What is performance appraisal?

Performance appraisal refers to overall review of the employee working for the organisation within a particular time period. Performance appraisal is measured by various aspects such as overall performance of the employee, task completed on time, work ethics, adaptability, helping others, increasing productivity these all aspects comes under performance appraisal.
Performance appraisal gives employees their overall report card of their work done in the organization during a particular time period, generally performance appraisals are done yearly.