F R E Q U E N C Y
All vibrations have amplitude and frequency. And in our energetic reality, all is vibrating. We are (as Nikola Tesla said) mere radio receivers who tune in to certain frequencies, and pick up the various stations. This creates our reality. Just consider the story of UFO believers, like the documentary movie 'Patient 17' which I just started playing. Oddly enough, the introductory scene of the movie plays such a 'radio receiver' sound fragment.
Now most of us humans are not UFO believers, and information regarding this subject on the Web is open to various interpretations. Some UFO movies I can easily recognize as the reflection of a ceiling light in a living room window, but there are also unexplained observations: some can be explained, but quite often the explanations are too obviously incorrect to cover the event.
Funny thing is lack of frequencies also tells us things: if a material absorbs certain frequency bands, we can deduce which elements are present.