The Lenovo Thinkcentre M53 Tiny has a Flash storage medium which is faster than most PCs of a comparable age and spec to it. Most PCs of this age and type have an HDD storage medium. Flash Drives store information in transistors on a circuit board rather than on optical or magnetic media. This has the advantage of being much faster than a traditional HDD drive. Across all computers that are a similar age to the Thinkcentre M53 Tiny the storage speed ranges from HDD to SSD.
If the storage speed of this desktop computer is not fast enough for you then you might also want to look at the Asus CN60 (£134.29) (SSD) which also has a higher rating.