The HP EliteBook 725 has an SSD storage medium which is better than most notebook PCs of a similar age and spec to it. Most similar spec notebook PCs that were released more than two years ago have an HDD storage medium. Solid State Drives (SSD) store data in semiconductors on a circuit board rather than using magnetic or optical media. Solid State Drives have no moving parts which makes them very fast and reliable.
An SSD storage medium is in fact the best storage medium amongst all laptops that are a comparable age to the EliteBook 725.
Amongst comparable types of notebook PC the worst storage medium is HDD.