Why does deleted files also appear in directory

Question

For example consider that i have created a file temp.txt and delete it later, there is still an invisible file temp.txt~ Of course I can delete it but Why do i need to do it always, So how to avoid it..

Answer 1

The file with tilde is called backup file and made everytime you edited a file on an editor. If you want, you can recover the file from that backup. Otherwise, delete it also.

Answer 2

If you don't want it, open Gedit and go to Edit->Preferences->Editor and uncheck Create Backup Copy if it's checked.
Also you can open terminal and navigate to that dir then

rm *.ext~