Loop unrolling is an optimization technique used in programming to improve the performance of loops. Instead of executing a loop multiple times, the loop's body is expanded or "unrolled" so that it performs several iterations in a single pass. This reduces the overhead of loop control, such as incrementing counters and checking conditions, leading to faster execution. By decreasing the number of iterations, loop unrolling can enhance the efficiency of the code, especially in scenarios where the loop body is small and the number of iterations is known in advance. This technique is commonly applied in low-level programming and can be beneficial in performance-critical applications, such as those involving graphics processing or scientific computing.