The Latitude 14 E7440 has a better storage medium than most medium processor cores notebook PCs that were released around the same time as it. This laptop has an SSD storage media, whereas most notebook PCs of a similar age and type to it have an HDD storage media. 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 amongst all medium processor cores notebook PCs that are a comparable age to the Latitude 14 E7440.
An HDD storage media is the worst storage medium amongst similar types of notebook PC.