Other programs use "extended file attributes", a feature of all modern file systems (which few people seem to know about).
👍 Works for every kind of file, including text files (e.g. for ASCII art).
👎 Old file systems, like FAT32, often used in memory cards, don't support extended attributes.
👎 The normal "file copy" doesn't copy them. You have to explicitly copy with the "all attributes" option.
Lastly, some programs use an internal database.
👍 Super fast and efficient search
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