The ZBOX CI320 nano has an SSD storage medium which is faster than most medium processor core personal computers that are a similar age to it. Most personal computers of a comparable spec and age to it have an HDD storage medium. Solid State Drives (SSD) store information in transistors on a circuit board rather than on optical or magnetic media. This has the advantage of being much faster than a traditional HDD drive.
An SSD storage medium is in fact the best storage speed amongst all personal computers of a similar age and type to the ZBOX CI320 nano.
The worst storage speed amongst comparable types of PC is HDD.