What does wear leveling mean and what is its use?

Solid-state drives (SSDs) use NAND flash memory as the storage medium. One drawback of NAND flash is that its memory cells will eventually wear out. To extend the product’s lifespan, the SSD memory controller employs various advanced algorithms to evenly distribute stored data across all flash cells. This prevents any individual cell or group of cells from being "overused." The use of wear leveling technology is widespread and effective.