Standard lowshelf filter. Frequencies lower than the frequency get a boost, or an attenuation; frequencies over it are unchanged.
Audio and Control lines (visualized with blue and purple, respectively) are both analogous to an analog signal. They can be used interchangeably, and, for example, an Audio output (blue) can be connected to a Control input (purple), or vice-versa.
This Node has exactly 2 samples of latency (equals ~0.0045 milliseconds at 44.1 kHz).