Most of those models were not sold concurrently. The Apple II, II+, and IIe each replaced the previous model; the same was true of the IIc and IIc Plus. "//e" was an alternate textual rendering of IIe, not a separate model.
replyThe most Apple II models that were sold concurrently were the IIe Platinum, IIc Plus, and IIgs. (And this was around 1990, at which point there were far more models of Macintosh computers on the market.)
The 2 and 2+ were concurrent.
replyThe 2e, 2e enhanced, 2c, 2c+ and 2gs were concurrent.
I didn’t bother with Mac because I got tired of writing all the things.
//e was a separate model from the ][+
reply64kb RAM + 80col card vs 48kb/40col
Bad example, but very true with the Mac under sculley. When Jobs came back that was one of the things he greatly simplified
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