The Mac computer, just like the Windows computer, offers an application called the trash can to store those data files you delete from their original locations. And thus, if you find you have done some wrong deletions, there is still a chance for you to restore the data files from the trash can. But it is not wise to keep all the data files on the trash can forever. You need to empty the trash can sometimes, if there is nothing important.
The trash can on the Mac is just as the recycle bin on the Windows. So you can also refer to this article, if you have a Windows computer. And also the good way we are going to introduce to you can also be used on the Windows with a few differences.