What's a 686?

[Ben Luey <lueyb@gridley.ACNS.Carleton.edu>]

I just downloaded i686.rpm package, but when I tried to install it on my
k6 system, I get

package pan-0.8.1beta3-1 is for a different architecture


What is a 686? A P-3? p-2, a k-7? Thanks,

Ben