Standing Wave: When interfering waves, have the same amplitude and wavelength, the resultant interference pattern remains nearly stationary and is called a standing wave interference pattern, a nodal point is a point that remains at rest throughout the interference of the pulses.

Deconstructive Wave: When a crest and trough meet “the waves are out of phase” the energies combine work against each other – they tend to cancel out.

Constructive Wave: When a crest from one source meets a crest from another source, the energies combine to displace the medium (energies are the additive), the same thing occurs when trough meets trough.

How do noise canceling headphones use wave interference to eliminate unwanted sound?

The noise canceling headphones transmit equal but opposite wavelengths which cancel out the sound/noise just like how deconstructive waves work.

Periodic Wave Description: Wave recurring at regular intervals.

Pulse Wave Description: Non-repeating wave.

Longitude Wave Description: Several turns of the spring are compressed and let go. Disturbance is in the same direction as the direction of the travel, “Lengthwise.”

Transverse Wave Description: Spring is pulled sideways (disturbance is at right angle to the direction that the wave will travel).