rm -rf ${dir_name | file name}

-r
This is used to delete directories. Even if there is a directory in the directory, all deletion will be done.

-f
It is ok to delete the file on linux without confirmation. For example, when deleting a large number of files, it is commonly used option when it is troublesome to check each time. Also, no warning will be issued even if the file does not exist.

[vagrant@localhost tests]$ ls
dmm index.php test
[vagrant@localhost tests]$ rm -rf dmm
[vagrant@localhost tests]$ ls
index.php test