Often actions need to only occur if a certain condition is true
This is similar to an “if” statement in a programming language
In digital systems, this is often done via a control signal, called a control function
If the signal is 1, the action takes place
This is represented as:
P: R2 R1
Which means “if P = 1, then load the contents of register R1 into register R2”, i.e., if (P = 1) then (R2 R1)