The EliteBook 820 G1 has an SSD storage medium which is better than the HDD storage medium found on most laptops of a similar type and age to it. 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 notebook PC's storage medium (SSD) is in fact the best storage medium across all comparable spec notebook PCs that were launched more than two years ago.
The worst storage medium amongst similar types of notebook PC is HDD.
If the storage medium of this portable PC is not good enough for you then you might want to consider the T420s (£1,388.87) (SSD), or the S540 (SSD) both from Lenovo.