Final answer:
During one period, a wave travels a distance equivalent to one wavelength, which is the space between two similar points like crests.
Step-by-step explanation:
The distance traveled by a wave during a single period is one wavelength. A wavelength is defined as the distance between two consecutive points of similar position along the wave, such as between two crests or two troughs. This distance also corresponds to the wave having completed one cycle, or one period. Therefore, when a wave completes one period, it has traveled a distance equal to one wavelength.