Application Performance Monitoring (APM) is a crucial practice that involves tracking and managing the performance of software applications to ensure they operate efficiently and effectively. APM tools provide insights into various metrics, such as response times, error rates, and transaction speeds, allowing developers to identify and resolve issues before they impact users. By monitoring application behavior in real-time, APM helps teams understand how their software performs under actual user conditions, rather than relying solely on synthetic tests. This proactive approach is essential for maintaining high-quality user experiences and optimizing application performance in production environments.