system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: How does emptying the recycle bin on your computer work?

What happens to the files? Where do they go?
gpt
Your hard drive is like a book with a table of contents in the front.

When you write a file to the hard drive you've essentially written a page in the book, plus you've made an entry to the table of contents.  Writing the page in the book takes some time, but there's no way around that.

Then, when you delete it you go to the table of contents and you put an asterisk next to that entry that says "Hey, this is in the recycle bin now."

When you delete the file from the recycle bin you go to the table of contents and you erase the entry.  Note that the page is still written with all the data, which is how un-deleting applications are able to restore files.  At this point if you were to need to write another page you might select that page and write over it (our pencil in this case has the magical property of erasing whatever is already on the page as you write).

There's one more level of deleting, which is offered by some programs:  you erase the entry in the table of contents, then you go to the page and you erase everything on the page.  It has, in the past, been possible to still recover some data left on the page (hard drives are actually analog media, although they are used to store digital data).  If you erase pencil from paper you're left with paper that is more blank than it is filled with writing, but under the right light you can see what was written before.  Similarly, when you write all zeroes in a section of the hard drive you have a bunch of values that are closer to 0 than anything else, but a sensitive tool could tell the difference between a 0 that was overwritten with a 0 and a 1 that was overwritten by a 0.  Modern hard drives tend to be too dense for this to work.  To combat this some programs will write over the page with all zeroes, all ones, random combinations of zeroes and ones, and so on.  This is obviously the slowest option, but for the very paranoid it offers peace of mind that the file has been completely deleted.