SDD, HDD hard drives
A hard drive is storage device that is used for storing data. SDD is almost like a HDD but is faster and could be used on mobile phones and computers e.g iphone 5, macbook air and nexus 5. An Input device is a device that can be used to insert data into a computer or other computational device. An output device is a device that is used to transfer data like images, documents and sounds.
An optical drive is a disk drive that uses a laser light or a electromagnetic waves within or near the visible light pectrum.