Whiskers, white and pointed, scientific name Vibrassae they pick up on vibrations in the air, see Wikipedia :

This vibration gives whiskers their scientific name, vibrissae, from the Latin word vibrio, meaning “to vibrate.” Detecting subtle changes in air currents, cat whiskers transmit information about the size, shape, and speed of nearby objects, which helps cats navigate the world.

They are also used to express the cats emotions. When I try and stroke my cars cheek the whiskers pull backwards. When they are interested or annoyed the whiskers come forward, especially when sniffing something. And they are supposed to stick out sideways to measure the size of a gap they can get through (although cats are thinner than they look, you can see that when they get very wet!). And don’t forget the whiskers above their eyes too..