Use After Free is a type of programming error that occurs when a program continues to use a memory location after it has been freed or deallocated. This can lead to unpredictable behavior, crashes, or security vulnerabilities, as the memory may be reallocated for other purposes. When a program frees memory, it signals that the space is available for reuse. If the program later tries to access this memory, it may retrieve invalid data or corrupt other data. Proper memory management practices, such as setting pointers to null after freeing, can help prevent Use After Free issues.