Digital vs Analog

"Digital": Redstone interpreted as either being unpowered (zero strength signal) or powered (any other strength signal). Buses only communicate digital redstone signals, and when passed back to redstone lines [through a Splitter(2) or an OutputBitSelect(i, n)], High/On/1 becomes a strength-15 signal, and Low/Off/0 becomes a strength-zero signal.

"Analog": Redstone signals, taking signal strength into account. Within a circuit's Implementation.class, these are usually represented as {bytes/shorts/ints/longs} with width overridden to 4. Using an Analog-To-Digital converter, a strength-15 signal translates to 1111b, and a Strength-0 signal translates to 0000b.