Which wave is known for having abrupt transitions back and forth between two voltage levels?

The square wave is characterized by its very distinct and sharp transitions between two voltage levels, typically high and low. This rapid switching creates a waveform that alternates sharply between these two states, producing a rectangular appearance. The abruptness of these transitions allows square waves to be particularly useful in digital signals and clock timings in electronic circuits, where clear, defined states are necessary for accurate signal processing.

Square waves are commonly utilized in various applications like digital electronics, where they represent binary data or clock pulses. Their unique shape can effectively toggle between states with little transitional time, making them ideal for triggering mechanisms in flip-flops, timers, and oscillators. In contrast, sine, triangular, and pulse waves exhibit smoother transitions or may not alternate between two strict voltage levels as precisely as square waves do.