system
Given the following post, respond as if you're commenting on Reddit:
human
Do two waves have to have the same frequency for interference to happen?

I can't find a clear answer to that.

If i understood it right, fourier synthesis lets a bunch of waves with different frequencies interfere to model a complex one. So it should be possible for two waves with different frequencies to interfere, right?
gpt
Waves with different frequencies can indeed interfere. In acoustics, the interference between two sounds of close (but not equal) frequency is known as a *beat*, being perceived as a single tone with varying volume. If the frequencies are a little further apart you can instead get a *combination tone* related to the difference between the frequencies.