No computer can surely function without a Trdi disk there. The Hard Disk Drive is one of the key parts of a computer. It is the component that allows and enables the storage of the data for a long term. It also has different applications and operating systems stored in it. All the information possible that you could save on your computer is because of the Hard Drive. It is considered to be the second memory to the računalnik. Even after you switch off the computer the data remains in the Hard Drive and does not get deleted.