Storage system including host device and storage device configured to perform selective purge operation

A storage system includes a host device and a storage device. The host device generates a write command, a logical address of write data corresponding to the write command, and a selective purge tag indicating that the write data are targeted for selective purge. The storage device receives the write command, the logical address, and the selective purge tag, stores write data, and logically erases the stored write data upon receiving an erase command from the host device. In addition, the storage device physically erases the stored write data upon receiving a selective purge request from the host device.