The HP Stream Mini 200 has an SSD storage medium which is faster than most few processor core PCs that have been available for around the same time as it. Most similar spec computers that have been on the market for around the same time as 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.
This personal computer's storage speed (SSD) is in fact the best storage speed across all desktop computers of a comparable type and age to the Stream Mini 200.
The worst storage speed across similar types of personal computer is HDD.