The TravelMate TMP645-MG has an SSD storage medium which is better than the HDD storage medium found on most notebook PCs of a comparable spec 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.
An SSD storage medium is in fact the best storage medium across all laptops of a comparable type and age to the TravelMate TMP645-MG.
An HDD storage medium is the worst storage medium across similar types of portable PC.
If the storage medium of this medium processor core notebook PC is too bad for you then you might also want to look at the T420s (£972.00) (SSD), or the X1 Carbon (£2,116.07) (SSD) both from Lenovo.