TRIM is simply a way for the operating system to tell the drive firmware about discarded sectors on the media.

So when one deletes a file, the O/S could issue some TRIM commands to inform the SSD firmware that the data in those sectors is no longer relevant.

The firmware can then use this knowledge to make more intelligent decisions about wear-leveling, garbage collection, and so forth.

Otherwise, without TRIM, the SSD firmware *must* assume that any sector that has *ever* been written to by sofware, still holds valid data. Forever. And cannot be erased/cycled without first copying the data elsewhere.

So TRIM is potentially a huge win for drive wear-leveling and overall performance.

Cheers