It's digital and analog. At the level of the action potential, the brain certainly does seem to operate with discreet units of information. Everywhere else though is certainly analog.
So if a neuron fires or not (I guess that's what you mean by action potential) can simply be translated to 1 or 0 hence it's digital?
Basically yes. That's only one small piece of the information processing of the brain, but it would in principal be possible to represent the "firing state" of a biological neural network in binary terms.