I have few directories contains databases backup: Code: [email protected]:/mnt/disk/backups# ls mysql_backup-18-05-16-02:00:01 mysql_backup-18-05-18-02:00:01 mysql_backup-18-05-20-02:00:01 mysql_backup-18-05-17-02:00:01 mysql_backup-18-05-19-02:00:01 mysql_backup-18-05-21-02:00:01 I have an array: Code: var=($(ls)) which contains mentioned above few directories in /mnt/disk/backups directory. I would like to remove from disk only first directory which is first element of the array $var: Code: rm -r ${var[0]} but I am not sure that this is good way to do it, although it is working. I am reading that this variable can be left in ram memory. Is that right and my way is good or bad? PS I tried with unset function but without success: Code: [email protected]:/mnt/disk/backups# unset ${var[@]} -bash: unset: `mysql_backup-18-05-16-02:00:01': not a valid identifier -bash: unset: `mysql_backup-18-05-17-02:00:01': not a valid identifier -bash: unset: `mysql_backup-18-05-18-02:00:01': not a valid identifier -bash: unset: `mysql_backup-18-05-19-02:00:01': not a valid identifier -bash: unset: `mysql_backup-18-05-20-02:00:01': not a valid identifier -bash: unset: `mysql_backup-18-05-21-02:00:01': not a valid identifier