The History page in the DB Backup Tool administration panel shows you a history of the previous backups you created, so for every backup you can see the date and time when it was made and you have also a download button allowing you to download it again.
This functionality can be useful also when you would like to keep multiple previous backups of the databases on the server (for example weekly backups), so you can download and restore in the future a backup made on some particular date you prefer.
If you wish your backup to not show up on the History page, you need to unckeck the checkbox "Save the backup in the history" on the Export page when creating the database backup.