They are extremely similar.
They still talk to each other.
What difference does there make if there are a few minor differences?
Is the Ti-86 discontinued or something? When I was in high school, we were told to buy that calculator for our math careers, but now I see a bunch of those Ti-84's instead.
Wouldn't a lower model number in this situation dictate some missing features...does anyone understand the difference between the two?
I own an 86 and love it. I prefer it by far over all other TI models short of the Voyage (even though it uses the 89's terrible OS) and the Nspire. I hate their OSs, but the Voyage's keyboard and the Nspire's grayscale screen are just too good to pass up.