Performance management is a process that provides feedback and accountability to help employees achieve organizational goals. It involves planning goals, regularly assessing performance through appraisals, and providing coaching like mentoring and feedback. At Apple, performance management is used to align individual objectives with company goals. Planning involves jointly setting clear goals, appraisals are ongoing and use peer reviews and 360 degree feedback, and coaching provides leadership, mentoring, and open communication. Performance is regularly evaluated and rewarded, and coaching helps underperforming employees improve.