Lending, or just been given a USB stick from someone, can be hazardous from your computer’s health.
You’ve heard of the car-park study where security researchers dropped a handful of USB keys in a company car-pack, and just waited for some silly people to go
“Oh look! Free USB stick! Lucky Me!”
And plug them into their work PC.
This post isn’t about that.
These files are created by Mac OS X to assist with searching, file modification and deletion tracking and desktop incon placement.
You can safely delete them.