If I, for example, set the voltage of the base of a transistor to 50% duty, will the collecter emitter voltage also be 50% of what it would normally be?
< If Arduino analog PWM voltage is put into the base of the transistor, will the collecter emitter voltage also be analog?
all digital signals are analog in that they are some levels of voltage or current.
whether a signal is analog or digital will depend on how such a signal is interpreted. if a 1.1v signal is interpreted differently than a 1.0v signal, that's considered "analog" - where the levels of the signal have meanings.
conversely, if levels of signals are meaningful only if the differences are substantial, that's a digital signal.
fundamentally, that's why a digital signal, or a digital process, is more robust and resistant to noise.