if I download from usb stick will it be empty ?

I'm an ESL teacher. Some months ago I had someone download some books I had on a USB stick onto a computer I using at that time. Yesterday I tried to download the books onto another computer and was told that there is nothing on it. It is empty ! We tried it on 2 other computers as well. Nothing !
I don't understand why.
Help !

be more specific:
- what website/company you used to download those books?
- what book reader you are using?
- did you copy or cut the files earlier from the USB?

be more specific:
- what website/company you used to download those books?
- what book reader you are using?
- did you copy or cut the files earlier from the USB?

Sorry, I don't know about this stuff. A couple of years ago someone downloaded these ESL teaching books for me from his USB to mine.
Then someone else downloaded them onto a class computer I was using in class last year.
Now I'm in a different place and I just wanted to give them to somebody else to print out. And he told me there's nothing on it and gave it back. I just tried on another computer and this guy says there is nothing on it , so I don't get it.

Who ever copied those books from the USB to the computer didn't actually do a copy, they more likely just moved the files from the USB to the computer, which obviously removed the files from the USB.

The only way you'll be able to get them back is to download those books again and copy them to the USB.

Who ever copied those books from the USB to the computer didn't actually do a copy, they more likely just moved the files from the USB to the computer, which obviously removed the files from the USB.

The only way you'll be able to get them back is to download those books again and copy them to the USB.

o.k. That's what I was afraid of. So , how can that be avoided in the future ? If I can go back and find the computer they are in, and put them back on my USB, how can I keep that from happening again? Can I let somebody else copy them without leaving it empty again ?

Thanks.

I'd suggest reading up on how to copy files from one place to another, I found a page here that explains it:
How to copy files

Either that or the files/folders are marked HIDDEN (I have seen some malware do this). Go to control panel -> Folder options (or File Explorer options under Win10) and, under the VIEW tab, select "Show files, folder and hidden drives".

O.K. Thanks

I'd suggest reading up on how to copy files from one place to another, I found a page here that explains it:
How to copy files

Either that or the files/folders are marked HIDDEN (I have seen some malware do this). Go to control panel -> Folder options (or File Explorer options under Win10) and, under the VIEW tab, select "Show files, folder and hidden drives".

O.K. Thanks, I'll check that out.

o.k. That's what I was afraid of. So , how can that be avoided in the future ? If I can go back and find the computer they are in, and put them back on my USB, how can I keep that from happening again? Can I let somebody else copy them without leaving it empty again
Thanks.

In case it does ever happen again. Back your files up so that you can just copy them back onto a USB stick. They are obviously important and all important files should have a backup.

Edit: You can also buy really cheap USB sticks these days. So have a couple you can lend out. If one gets lost, files deleted or infected with a virus it is not a big deal.