Load testing tools are software applications designed to evaluate how a system performs under heavy user demand. They simulate multiple users accessing the system simultaneously to identify performance bottlenecks, response times, and overall stability. Commonly used in web applications, these tools help ensure that a system can handle expected traffic without crashing or slowing down. Some popular load testing tools include Apache JMeter, LoadRunner, and Gatling. These tools provide features like real-time monitoring, detailed reporting, and the ability to create custom test scenarios. By using load testing tools, organizations can improve their systems' reliability and enhance user experience.