Difference between Display Attribute and Navigational Attribute?

The basic difference between the two is that navigational attributes can be used to drilldown in a Bex report whereas display attributes cannot be used so. A navigational attribute would function more or less like a characteristic within a cube.
To enable these features of a navigational attribute, the attribute needs to be made navigational in the cube apart from the master data info-object.
The only difference is that navigation attributes can be used for navigation in queries, like filtering, drill-down etc.
You can also use hierarchies on navigational attributes, as it is possible for characteristics.
But an extra feature is that there is a possibility to change your history. (Please look at the relevant time scenarios). If navigation attributes changes for a characteristic, it is changed for all records in the past. Disadvantage is also a slow down in performance.