A hard drive is a disk drive thats used to store files and data on your computer.There are quite a few different types of hard drive for example: SSD and HDD.All of these devices are used differently. SSD are used because they are extremly fast, HDD is used to access files or programs.
An optical drive is a type of computer disk drivr that reads and writes data from any optical disk. Some drives ca only read disks but recent drives are readers and recorders. They are maily used in computers to watch or read CD, BLUE-RAY and DVD.