About SSD Trim:

SSD trim will erase/wipe unused blocks from the SSD, So that deleted data is not shuffled around the drive.
Plus is better for privacy since deleted data is not recoverable since it is erased/wiped.

Unfortunately trim is activated in limited Scenarios though:

The drive must be internal (connected to a SATA or NVMe bus).
Connected to a USB port will not work. So its imposable to use trim on a USB Flash Drive or SD card.
Including using a external USB SSD since the OS cant detect that its an SSD (Thinks its a HDD).
You must use a supported file system. If there is no file system on that partition, or its not a supported FS (like FAT32), trim will not work on that portion of the drive.
The drive must be mounted when trim is ran. or else it will be ignored until next trim.
Some file systems, like ext4 or NTFS, will not run trim automatically when a file is deleted. It must be ran manually. (F2FS does do it automatically).

Date: June 16th 2024

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