The HP EliteBook 725 has an SSD storage medium which is better than the HDD storage medium found on most notebook PCs of this type and age. 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.
This laptop's storage medium (SSD) is in fact the best storage medium amongst all portable PCs of a similar type and age to the EliteBook 725.
Amongst comparable types of laptop the worst storage medium is HDD.