The Stream 11-d070nd has a better storage medium than most notebook PCs of a comparable age and spec to it. This portable PC has an SSD storage medium, whereas most portable PCs that were launched around the same time as it have an HDD storage medium. Flash drives store data in semiconductors on a circuit board rather than using magnetic or optical media. Flash have no moving parts which makes them very fast and reliable.
This notebook PC's storage medium (SSD) is actually the best storage medium amongst all portable PCs of this spec and age.
An HDD storage medium is the worst storage medium amongst comparable types of notebook PC.