Foo-bu. I'm not sure what thye reference to "click" is- ? a click track? But a pop filter does 3 things for you. The first, and its primary mission, is to reduce wind blasts that are discharged from aspirated consonants on close mic'd vocals. These consonants, "P" in particular, are also called 'plosives. Put your hand right in front of your mouth and recite "Peter picked a peck of pickled peppers" a few times. Really sensitive mics get blasted by this, producing a phenomenon called "pop", which is pretty much always bad.
Secondly, a pop filter keeps you from inadvertently spitting on the diaphragm of your expensive condenser mic, which is bad for it. Third, the pop filter gives the singer a reference point relative to the mic, which is helpful in maintaining the correct distance between the singer and the mic. This distance can vary quite a bit, depending on the mic, the singer, and the material.
Most stage mics have some sort of pop filter built into the housing, but most studio condensers don't. Hope this helps.-Richie