The Asus Chromebox M077U has an SSD storage medium which is faster than the HDD storage medium found on most comparable spec desktop computers that were launched around the same time as it. 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.
This PC's storage speed (SSD) is actually the best storage speed amongst all few processor core PCs that were launched around the same time as the Chromebox M077U.
Amongst similar types of PC the worst storage speed is HDD.