Branch on result zero.

Could also be called "Branch on Equal".

Take a conditional branch if the zero bit is set (1)

Table

BEQ | Branch on Result Zero (on Equal)
================================================

                                 N V - B D I Z C
                                 - - - - - - - -

addressing       assembler    opc  bytes  cycles
------------------------------------------------
relative         BEQ $nnnn    F0     2     2 tp

p: +1 if page is crossed
t: +1 if branch is taken