The EliteBook 840 has an SSD storage medium which is better than most similar spec portable PCs that have been available for more than two years. Most medium processor core laptops that came out around the same time as it 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.
This portable PC's storage medium (SSD) is in fact the best storage medium across all laptops of this age and type.
The worst storage medium across comparable types of portable PC is HDD.
We think you might also be interested in some of the other portable PCs that have an SSD storage media currently available including the HP EliteBook 840[plb_2320440_price], or the DELL XPS 13[plb_1304263_price] which is cheaper.
If the storage medium of this HP laptop is not good enough for you then you might also want to consider the T420s[pl_48433_price] (SSD), or the X1[pl_1610908_price] (SSD) both from Lenovo.