Java Concurrency is a feature in the Java programming language that allows multiple threads to run simultaneously. This capability helps improve the performance of applications by enabling them to perform tasks in parallel, making better use of system resources. In Java, concurrency is managed through various classes and interfaces, such as Thread, Runnable, and ExecutorService. These tools help developers create, manage, and synchronize threads, ensuring that shared resources are accessed safely and efficiently, thus preventing issues like data corruption or inconsistent results.