In the past, the high-end line was the 6 series, being the C6x0, D6x0, and E64x0 lines, but as of 2015 this line has been discontinued and replaced by both the 5 series and the 7 series. The Latitudes from the early 1990s up until the C*00 lines weren't in a set 'series', instead of going under the models CP and XP with modifiers at the end, e.g.: XPi, CP M233. The Dell Latitude series have dropped the initial alphabet in newer model types (as in Latitude 7480 whose predecessor was E7470), and became the successor to the popular Latitude E, D, C, and X series.
