To find the period of a wave, you can use the formula:
\[ \text{Period} (T) = \frac{1}{\text{Frequency} (f)} \]
Given that the frequency \( f \) is 0.5 hertz, we can substitute this value into the formula:
\[ T = \frac{1}{0.5} = 2 \text{ seconds} \]
Therefore, the period of the wave is 2 seconds.