The storage speed of this personal computer is HDD, which is the most frequently found storage medium on personal computers of a similar spec and age to it. A Hard Disk Drive (HDD) is the traditional storage method for computers. A HDD stores the information on magnetic disks. HDD drives are cheap, but they are slower than Flash and SSD bases storage systems.
It may also be worth also looking at one of the other HDD desktop computers currently available including cheaper desktop computers such as the HP ProDesk 600 SFF.
If the storage speed of this HP computer is too slow for you then you might also want to consider the HP EliteDesk 800 G1 Mini (SSD) which is also cheaper.